diff --git a/retrieval/discovery/consul.go b/retrieval/discovery/consul.go
index 3e2f856f08..172c760a32 100644
--- a/retrieval/discovery/consul.go
+++ b/retrieval/discovery/consul.go
@@ -66,7 +66,7 @@ type ConsulDiscovery struct {
 // consulService contains data belonging to the same service.
 type consulService struct {
 	name      string
-	tgroup    *config.TargetGroup
+	tgroup    config.TargetGroup
 	lastIndex uint64
 	removed   bool
 	running   bool
@@ -143,7 +143,7 @@ func (cd *ConsulDiscovery) Sources() []string {
 }
 
 // Run implements the TargetProvider interface.
-func (cd *ConsulDiscovery) Run(ch chan<- *config.TargetGroup, done <-chan struct{}) {
+func (cd *ConsulDiscovery) Run(ch chan<- config.TargetGroup, done <-chan struct{}) {
 	defer close(ch)
 	defer cd.stop()
 
@@ -159,7 +159,7 @@ func (cd *ConsulDiscovery) Run(ch chan<- *config.TargetGroup, done <-chan struct
 				close(srv.done)
 
 				// Send clearing update.
-				ch <- &config.TargetGroup{Source: srv.name}
+				ch <- config.TargetGroup{Source: srv.name}
 				break
 			}
 			// Launch watcher for the service.
@@ -219,9 +219,8 @@ func (cd *ConsulDiscovery) watchServices(update chan<- *consulService, done <-ch
 			srv, ok := cd.services[name]
 			if !ok {
 				srv = &consulService{
-					name:   name,
-					tgroup: &config.TargetGroup{},
-					done:   make(chan struct{}),
+					name: name,
+					done: make(chan struct{}),
 				}
 				srv.tgroup.Source = name
 				cd.services[name] = srv
@@ -246,7 +245,7 @@ func (cd *ConsulDiscovery) watchServices(update chan<- *consulService, done <-ch
 
 // watchService retrieves updates about srv from Consul's service endpoint.
 // On a potential update the resulting target group is sent to ch.
-func (cd *ConsulDiscovery) watchService(srv *consulService, ch chan<- *config.TargetGroup) {
+func (cd *ConsulDiscovery) watchService(srv *consulService, ch chan<- config.TargetGroup) {
 	catalog := cd.client.Catalog()
 	for {
 		nodes, meta, err := catalog.Service(srv.name, "", &consul.QueryOptions{
diff --git a/retrieval/discovery/dns.go b/retrieval/discovery/dns.go
index 7e4cb235be..40a8841e1f 100644
--- a/retrieval/discovery/dns.go
+++ b/retrieval/discovery/dns.go
@@ -91,7 +91,7 @@ func NewDNSDiscovery(conf *config.DNSSDConfig) *DNSDiscovery {
 }
 
 // Run implements the TargetProvider interface.
-func (dd *DNSDiscovery) Run(ch chan<- *config.TargetGroup, done <-chan struct{}) {
+func (dd *DNSDiscovery) Run(ch chan<- config.TargetGroup, done <-chan struct{}) {
 	defer close(ch)
 
 	ticker := time.NewTicker(dd.interval)
@@ -119,7 +119,7 @@ func (dd *DNSDiscovery) Sources() []string {
 	return srcs
 }
 
-func (dd *DNSDiscovery) refreshAll(ch chan<- *config.TargetGroup) {
+func (dd *DNSDiscovery) refreshAll(ch chan<- config.TargetGroup) {
 	var wg sync.WaitGroup
 	wg.Add(len(dd.names))
 	for _, name := range dd.names {
@@ -133,7 +133,7 @@ func (dd *DNSDiscovery) refreshAll(ch chan<- *config.TargetGroup) {
 	wg.Wait()
 }
 
-func (dd *DNSDiscovery) refresh(name string, ch chan<- *config.TargetGroup) error {
+func (dd *DNSDiscovery) refresh(name string, ch chan<- config.TargetGroup) error {
 	response, err := lookupAll(name, dd.qtype)
 	dnsSDLookupsCount.Inc()
 	if err != nil {
@@ -141,7 +141,7 @@ func (dd *DNSDiscovery) refresh(name string, ch chan<- *config.TargetGroup) erro
 		return err
 	}
 
-	tg := &config.TargetGroup{}
+	var tg config.TargetGroup
 	for _, record := range response.Answer {
 		target := model.LabelValue("")
 		switch addr := record.(type) {
diff --git a/retrieval/discovery/ec2.go b/retrieval/discovery/ec2.go
index 795355509e..193a68ab77 100644
--- a/retrieval/discovery/ec2.go
+++ b/retrieval/discovery/ec2.go
@@ -62,7 +62,7 @@ func NewEC2Discovery(conf *config.EC2SDConfig) *EC2Discovery {
 }
 
 // Run implements the TargetProvider interface.
-func (ed *EC2Discovery) Run(ch chan<- *config.TargetGroup, done <-chan struct{}) {
+func (ed *EC2Discovery) Run(ch chan<- config.TargetGroup, done <-chan struct{}) {
 	defer close(ch)
 
 	ticker := time.NewTicker(ed.interval)
@@ -73,7 +73,7 @@ func (ed *EC2Discovery) Run(ch chan<- *config.TargetGroup, done <-chan struct{})
 	if err != nil {
 		log.Error(err)
 	} else {
-		ch <- tg
+		ch <- *tg
 	}
 
 	for {
@@ -83,7 +83,7 @@ func (ed *EC2Discovery) Run(ch chan<- *config.TargetGroup, done <-chan struct{})
 			if err != nil {
 				log.Error(err)
 			} else {
-				ch <- tg
+				ch <- *tg
 			}
 		case <-done:
 			return
diff --git a/retrieval/discovery/file.go b/retrieval/discovery/file.go
index 44dc240aa0..eb0411b30f 100644
--- a/retrieval/discovery/file.go
+++ b/retrieval/discovery/file.go
@@ -103,7 +103,7 @@ func (fd *FileDiscovery) watchFiles() {
 }
 
 // Run implements the TargetProvider interface.
-func (fd *FileDiscovery) Run(ch chan<- *config.TargetGroup, done <-chan struct{}) {
+func (fd *FileDiscovery) Run(ch chan<- config.TargetGroup, done <-chan struct{}) {
 	defer close(ch)
 	defer fd.stop()
 
@@ -188,7 +188,7 @@ func (fd *FileDiscovery) stop() {
 
 // refresh reads all files matching the discovery's patterns and sends the respective
 // updated target groups through the channel.
-func (fd *FileDiscovery) refresh(ch chan<- *config.TargetGroup) {
+func (fd *FileDiscovery) refresh(ch chan<- config.TargetGroup) {
 	ref := map[string]int{}
 	for _, p := range fd.listFiles() {
 		tgroups, err := readFile(p)
@@ -199,7 +199,7 @@ func (fd *FileDiscovery) refresh(ch chan<- *config.TargetGroup) {
 			continue
 		}
 		for _, tg := range tgroups {
-			ch <- tg
+			ch <- *tg
 		}
 		ref[p] = len(tgroups)
 	}
@@ -208,7 +208,7 @@ func (fd *FileDiscovery) refresh(ch chan<- *config.TargetGroup) {
 		m, ok := ref[f]
 		if !ok || n > m {
 			for i := m; i < n; i++ {
-				ch <- &config.TargetGroup{Source: fileSource(f, i)}
+				ch <- config.TargetGroup{Source: fileSource(f, i)}
 			}
 		}
 	}
diff --git a/retrieval/discovery/file_test.go b/retrieval/discovery/file_test.go
index 0335013b1e..74270ad029 100644
--- a/retrieval/discovery/file_test.go
+++ b/retrieval/discovery/file_test.go
@@ -26,7 +26,7 @@ func testFileSD(t *testing.T, ext string) {
 
 	var (
 		fsd  = NewFileDiscovery(&conf)
-		ch   = make(chan *config.TargetGroup)
+		ch   = make(chan config.TargetGroup)
 		done = make(chan struct{})
 	)
 	go fsd.Run(ch, done)
diff --git a/retrieval/discovery/kubernetes/discovery.go b/retrieval/discovery/kubernetes/discovery.go
index dce1b9ccd0..5438f6f21d 100644
--- a/retrieval/discovery/kubernetes/discovery.go
+++ b/retrieval/discovery/kubernetes/discovery.go
@@ -173,25 +173,35 @@ func (kd *Discovery) Sources() []string {
 }
 
 // Run implements the TargetProvider interface.
-func (kd *Discovery) Run(ch chan<- *config.TargetGroup, done <-chan struct{}) {
+func (kd *Discovery) Run(ch chan<- config.TargetGroup, done <-chan struct{}) {
 	defer close(ch)
 
-	select {
-	case ch <- kd.updateMastersTargetGroup():
-	case <-done:
-		return
+	if tg := kd.updateMastersTargetGroup(); tg != nil {
+		select {
+		case ch <- *tg:
+		case <-done:
+			return
+		}
 	}
 
-	select {
-	case ch <- kd.updateNodesTargetGroup():
-	case <-done:
-		return
+	if tg := kd.updateNodesTargetGroup(); tg != nil {
+		select {
+		case ch <- *tg:
+		case <-done:
+			return
+		}
 	}
 
 	for _, ns := range kd.services {
 		for _, service := range ns {
+			tg := kd.addService(service)
+
+			if tg == nil {
+				continue
+			}
+
 			select {
-			case ch <- kd.addService(service):
+			case ch <- *tg:
 			case <-done:
 				return
 			}
@@ -223,8 +233,12 @@ func (kd *Discovery) Run(ch chan<- *config.TargetGroup, done <-chan struct{}) {
 			}
 		}
 
+		if tg == nil {
+			continue
+		}
+
 		select {
-		case ch <- tg:
+		case ch <- *tg:
 		case <-done:
 			return
 		}
diff --git a/retrieval/discovery/marathon.go b/retrieval/discovery/marathon.go
index ca89b91ea5..181ea440f4 100644
--- a/retrieval/discovery/marathon.go
+++ b/retrieval/discovery/marathon.go
@@ -53,7 +53,7 @@ func (md *MarathonDiscovery) Sources() []string {
 }
 
 // Run implements the TargetProvider interface.
-func (md *MarathonDiscovery) Run(ch chan<- *config.TargetGroup, done <-chan struct{}) {
+func (md *MarathonDiscovery) Run(ch chan<- config.TargetGroup, done <-chan struct{}) {
 	defer close(ch)
 
 	for {
@@ -69,7 +69,7 @@ func (md *MarathonDiscovery) Run(ch chan<- *config.TargetGroup, done <-chan stru
 	}
 }
 
-func (md *MarathonDiscovery) updateServices(ch chan<- *config.TargetGroup) error {
+func (md *MarathonDiscovery) updateServices(ch chan<- config.TargetGroup) error {
 	targetMap, err := md.fetchTargetGroups()
 	if err != nil {
 		return err
@@ -77,7 +77,7 @@ func (md *MarathonDiscovery) updateServices(ch chan<- *config.TargetGroup) error
 
 	// Update services which are still present
 	for _, tg := range targetMap {
-		ch <- tg
+		ch <- *tg
 	}
 
 	// Remove services which did disappear
@@ -85,7 +85,7 @@ func (md *MarathonDiscovery) updateServices(ch chan<- *config.TargetGroup) error
 		_, ok := targetMap[source]
 		if !ok {
 			log.Debugf("Removing group for %s", source)
-			ch <- &config.TargetGroup{Source: source}
+			ch <- config.TargetGroup{Source: source}
 		}
 	}
 
diff --git a/retrieval/discovery/marathon_test.go b/retrieval/discovery/marathon_test.go
index 6dd731e98c..f54d828077 100644
--- a/retrieval/discovery/marathon_test.go
+++ b/retrieval/discovery/marathon_test.go
@@ -26,8 +26,8 @@ import (
 
 var marathonValidLabel = map[string]string{"prometheus": "yes"}
 
-func newTestDiscovery(client marathon.AppListClient) (chan *config.TargetGroup, *MarathonDiscovery) {
-	ch := make(chan *config.TargetGroup)
+func newTestDiscovery(client marathon.AppListClient) (chan config.TargetGroup, *MarathonDiscovery) {
+	ch := make(chan config.TargetGroup)
 	md := NewMarathonDiscovery(&config.MarathonSDConfig{
 		Servers: []string{"http://localhost:8080"},
 	})
diff --git a/retrieval/discovery/serverset.go b/retrieval/discovery/serverset.go
index 0e12656165..21bdb6b047 100644
--- a/retrieval/discovery/serverset.go
+++ b/retrieval/discovery/serverset.go
@@ -67,7 +67,7 @@ type ServersetDiscovery struct {
 	conn       *zk.Conn
 	mu         sync.RWMutex
 	sources    map[string]*config.TargetGroup
-	sdUpdates  *chan<- *config.TargetGroup
+	sdUpdates  *chan<- config.TargetGroup
 	updates    chan zookeeperTreeCacheEvent
 	treeCaches []*zookeeperTreeCache
 }
@@ -124,7 +124,7 @@ func (sd *ServersetDiscovery) processUpdates() {
 		}
 		sd.mu.Unlock()
 		if sd.sdUpdates != nil {
-			*sd.sdUpdates <- tg
+			*sd.sdUpdates <- *tg
 		}
 	}
 
@@ -134,11 +134,11 @@ func (sd *ServersetDiscovery) processUpdates() {
 }
 
 // Run implements the TargetProvider interface.
-func (sd *ServersetDiscovery) Run(ch chan<- *config.TargetGroup, done <-chan struct{}) {
+func (sd *ServersetDiscovery) Run(ch chan<- config.TargetGroup, done <-chan struct{}) {
 	// Send on everything we have seen so far.
 	sd.mu.Lock()
 	for _, targetGroup := range sd.sources {
-		ch <- targetGroup
+		ch <- *targetGroup
 	}
 	// Tell processUpdates to send future updates.
 	sd.sdUpdates = &ch
diff --git a/retrieval/helpers_test.go b/retrieval/helpers_test.go
index 1e715d774f..880e6230c6 100644
--- a/retrieval/helpers_test.go
+++ b/retrieval/helpers_test.go
@@ -52,12 +52,12 @@ type fakeTargetProvider struct {
 	update  chan *config.TargetGroup
 }
 
-func (tp *fakeTargetProvider) Run(ch chan<- *config.TargetGroup, done <-chan struct{}) {
+func (tp *fakeTargetProvider) Run(ch chan<- config.TargetGroup, done <-chan struct{}) {
 	defer close(ch)
 	for {
 		select {
 		case tg := <-tp.update:
-			ch <- tg
+			ch <- *tg
 		case <-done:
 			return
 		}
diff --git a/retrieval/targetmanager.go b/retrieval/targetmanager.go
index 3f3a4377bd..f301b9a1b2 100644
--- a/retrieval/targetmanager.go
+++ b/retrieval/targetmanager.go
@@ -43,7 +43,7 @@ type TargetProvider interface {
 	// updated target groups. The channel must be closed by the target provider
 	// if no more updates will be sent.
 	// On receiving from done Run must return.
-	Run(up chan<- *config.TargetGroup, done <-chan struct{})
+	Run(up chan<- config.TargetGroup, done <-chan struct{})
 }
 
 // TargetManager maintains a set of targets, starts and stops their scraping and
@@ -105,7 +105,7 @@ func merge(done <-chan struct{}, cs ...<-chan targetGroupUpdate) <-chan targetGr
 // targetGroupUpdate is a potentially changed/new target group
 // for the given scrape configuration.
 type targetGroupUpdate struct {
-	tg   *config.TargetGroup
+	tg   config.TargetGroup
 	scfg *config.ScrapeConfig
 }
 
@@ -126,9 +126,9 @@ func (tm *TargetManager) Run() {
 				sources[src] = struct{}{}
 			}
 
-			tgc := make(chan *config.TargetGroup)
+			tgc := make(chan config.TargetGroup)
 			// Run the target provider after cleanup of the stale targets is done.
-			defer func(prov TargetProvider, tgc chan<- *config.TargetGroup, done <-chan struct{}) {
+			defer func(prov TargetProvider, tgc chan<- config.TargetGroup, done <-chan struct{}) {
 				go prov.Run(tgc, done)
 			}(prov, tgc, tm.done)
 
@@ -140,9 +140,6 @@ func (tm *TargetManager) Run() {
 				for {
 					select {
 					case tg := <-tgc:
-						if tg == nil {
-							break
-						}
 						tgupc <- targetGroupUpdate{tg: tg, scfg: scfg}
 					case <-done:
 						return
@@ -179,12 +176,9 @@ func (tm *TargetManager) handleUpdates(ch <-chan targetGroupUpdate, done <-chan
 			if !ok {
 				return
 			}
-			if update.tg == nil {
-				break
-			}
 			log.Debugf("Received potential update for target group %q", update.tg.Source)
 
-			if err := tm.updateTargetGroup(update.tg, update.scfg); err != nil {
+			if err := tm.updateTargetGroup(&update.tg, update.scfg); err != nil {
 				log.Errorf("Error updating targets: %s", err)
 			}
 		case <-done:
@@ -382,10 +376,10 @@ func (tp *prefixedTargetProvider) Sources() []string {
 	return srcs
 }
 
-func (tp *prefixedTargetProvider) Run(ch chan<- *config.TargetGroup, done <-chan struct{}) {
+func (tp *prefixedTargetProvider) Run(ch chan<- config.TargetGroup, done <-chan struct{}) {
 	defer close(ch)
 
-	ch2 := make(chan *config.TargetGroup)
+	ch2 := make(chan config.TargetGroup)
 	go tp.TargetProvider.Run(ch2, done)
 
 	for {
@@ -393,9 +387,6 @@ func (tp *prefixedTargetProvider) Run(ch chan<- *config.TargetGroup, done <-chan
 		case <-done:
 			return
 		case tg := <-ch2:
-			if tg == nil {
-				break
-			}
 			tg.Source = tp.prefix(tg.Source)
 			ch <- tg
 		}
@@ -537,14 +528,14 @@ func NewStaticProvider(groups []*config.TargetGroup) *StaticProvider {
 }
 
 // Run implements the TargetProvider interface.
-func (sd *StaticProvider) Run(ch chan<- *config.TargetGroup, done <-chan struct{}) {
+func (sd *StaticProvider) Run(ch chan<- config.TargetGroup, done <-chan struct{}) {
 	defer close(ch)
 
 	for _, tg := range sd.TargetGroups {
 		select {
 		case <-done:
 			return
-		case ch <- tg:
+		case ch <- *tg:
 		}
 	}
 	<-done
diff --git a/retrieval/targetmanager_test.go b/retrieval/targetmanager_test.go
index aa0cb188a9..3f605f7693 100644
--- a/retrieval/targetmanager_test.go
+++ b/retrieval/targetmanager_test.go
@@ -52,7 +52,7 @@ func TestPrefixedTargetProvider(t *testing.T) {
 		t.Fatalf("expected sources %v, got %v", expSources, tp.Sources())
 	}
 
-	ch := make(chan *config.TargetGroup)
+	ch := make(chan config.TargetGroup)
 	done := make(chan struct{})
 
 	defer close(done)
@@ -64,10 +64,10 @@ func TestPrefixedTargetProvider(t *testing.T) {
 	expGroup2.Source = "job-x:static:123:1"
 
 	// The static target provider sends on the channel once per target group.
-	if tg := <-ch; !reflect.DeepEqual(tg, &expGroup1) {
+	if tg := <-ch; !reflect.DeepEqual(tg, expGroup1) {
 		t.Fatalf("expected target group %v, got %v", expGroup1, tg)
 	}
-	if tg := <-ch; !reflect.DeepEqual(tg, &expGroup2) {
+	if tg := <-ch; !reflect.DeepEqual(tg, expGroup2) {
 		t.Fatalf("expected target group %v, got %v", expGroup2, tg)
 	}
 }