diff --git a/tsdb/index/postings.go b/tsdb/index/postings.go
index 61a5560ee..b48c086d5 100644
--- a/tsdb/index/postings.go
+++ b/tsdb/index/postings.go
@@ -487,15 +487,19 @@ func (it *intersectPostings) At() storage.SeriesRef {
 func (it *intersectPostings) doNext() bool {
 Loop:
 	for {
+		cont := false
 		for _, p := range it.arr {
 			if !p.Seek(it.cur) {
 				return false
 			}
 			if p.At() > it.cur {
 				it.cur = p.At()
-				continue Loop
+				cont = true
 			}
 		}
+		if cont {
+			continue Loop
+		}
 		return true
 	}
 }
diff --git a/tsdb/querier_bench_test.go b/tsdb/querier_bench_test.go
index 9a8230242..9294d8fcd 100644
--- a/tsdb/querier_bench_test.go
+++ b/tsdb/querier_bench_test.go
@@ -46,6 +46,7 @@ func BenchmarkQuerier(b *testing.B) {
 	}
 
 	for n := 0; n < 10; n++ {
+		addSeries(labels.FromStrings("a", strconv.Itoa(n)+postingsBenchSuffix))
 		for i := 0; i < 100000; i++ {
 			addSeries(labels.FromStrings("i", strconv.Itoa(i)+postingsBenchSuffix, "n", strconv.Itoa(n)+postingsBenchSuffix, "j", "foo"))
 			// Have some series that won't be matched, to properly test inverted matches.
@@ -98,7 +99,9 @@ func BenchmarkQuerier(b *testing.B) {
 func benchmarkPostingsForMatchers(b *testing.B, ir IndexReader) {
 	ctx := context.Background()
 
+	a1 := labels.MustNewMatcher(labels.MatchEqual, "a", "1"+postingsBenchSuffix)
 	n1 := labels.MustNewMatcher(labels.MatchEqual, "n", "1"+postingsBenchSuffix)
+	n0_1 := labels.MustNewMatcher(labels.MatchEqual, "n", "0_1"+postingsBenchSuffix)
 	nX := labels.MustNewMatcher(labels.MatchEqual, "n", "X"+postingsBenchSuffix)
 
 	jFoo := labels.MustNewMatcher(labels.MatchEqual, "j", "foo")
@@ -134,6 +137,7 @@ func benchmarkPostingsForMatchers(b *testing.B, ir IndexReader) {
 		{`j="foo",n="1"`, []*labels.Matcher{jFoo, n1}},
 		{`n="1",j!="foo"`, []*labels.Matcher{n1, jNotFoo}},
 		{`n="1",i!="2"`, []*labels.Matcher{n1, iNot2}},
+		{`n="0_1",j="foo,a="1"`, []*labels.Matcher{n0_1, jFoo, a1}},
 		{`n="X",j!="foo"`, []*labels.Matcher{nX, jNotFoo}},
 		{`i=~"1[0-9]",j=~"foo|bar"`, []*labels.Matcher{iCharSet, jFooBar}},
 		{`j=~"foo|bar"`, []*labels.Matcher{jFooBar}},
@@ -173,8 +177,12 @@ func benchmarkPostingsForMatchers(b *testing.B, ir IndexReader) {
 			b.ReportAllocs()
 			b.ResetTimer()
 			for i := 0; i < b.N; i++ {
-				_, err := PostingsForMatchers(ctx, ir, c.matchers...)
+				p, err := PostingsForMatchers(ctx, ir, c.matchers...)
 				require.NoError(b, err)
+				// Iterate over the postings
+				for p.Next() {
+					// Do nothing
+				}
 			}
 		})
 	}