diff --git a/internal/pool/pool_single.go b/internal/pool/pool_single.go
index 6f85b30..9474374 100644
--- a/internal/pool/pool_single.go
+++ b/internal/pool/pool_single.go
@@ -27,12 +27,12 @@ func (e BadConnError) Unwrap() error {
 }
 
 type SingleConnPool struct {
-	pool Pooler
+	pool  Pooler
+	level int32 // atomic
 
 	state uint32 // atomic
 	ch    chan *Conn
 
-	level         int32 // atomic
 	_badConnError atomic.Value
 }