diff --git a/tsdb/db.go b/tsdb/db.go
index 2d35e3fb00..ea8cbfff0b 100644
--- a/tsdb/db.go
+++ b/tsdb/db.go
@@ -992,9 +992,14 @@ func open(dir string, l *slog.Logger, r prometheus.Registerer, opts *Options, rn
 	db.metrics.maxBytes.Set(float64(maxBytes))
 	db.metrics.retentionDuration.Set((time.Duration(opts.RetentionDuration) * time.Millisecond).Seconds())
 
+	// Calling db.reload() calls db.reloadBlocks() which requires cmtx to be locked.
+	db.cmtx.Lock()
 	if err := db.reload(); err != nil {
+		db.cmtx.Unlock()
 		return nil, err
 	}
+	db.cmtx.Unlock()
+
 	// Set the min valid time for the ingested samples
 	// to be no lower than the maxt of the last block.
 	minValidTime := int64(math.MinInt64)
@@ -1568,13 +1573,9 @@ func (db *DB) reloadBlocks() (err error) {
 		db.metrics.reloads.Inc()
 	}()
 
-	// Now that we reload TSDB every minute, there is a high chance for a race condition with a reload
-	// triggered by CleanTombstones(). We need to lock the reload to avoid the situation where
-	// a normal reload and CleanTombstones try to delete the same block.
-	db.mtx.Lock()
-	defer db.mtx.Unlock()
-
+	db.mtx.RLock()
 	loadable, corrupted, err := openBlocks(db.logger, db.dir, db.blocks, db.chunkPool, db.opts.PostingsDecoderFactory)
+	db.mtx.RUnlock()
 	if err != nil {
 		return err
 	}
@@ -1643,8 +1644,10 @@ func (db *DB) reloadBlocks() (err error) {
 	})
 
 	// Swap new blocks first for subsequently created readers to be seen.
+	db.mtx.Lock()
 	oldBlocks := db.blocks
 	db.blocks = toLoad
+	db.mtx.Unlock()
 
 	// Only check overlapping blocks when overlapping compaction is enabled.
 	if db.opts.EnableOverlappingCompaction {