diff --git a/p2p/discv5/sim_test.go b/p2p/discv5/sim_test.go
index 543faecd48..76379452a5 100644
--- a/p2p/discv5/sim_test.go
+++ b/p2p/discv5/sim_test.go
@@ -50,7 +50,7 @@ func TestSimRandomResolve(t *testing.T) {
 			if err := net.SetFallbackNodes([]*Node{bootnode.Self()}); err != nil {
 				panic(err)
 			}
-			fmt.Printf("launched @ %v: %x\n", time.Now(), net.Self().ID[:16])
+			t.Logf("launched @ %v: %x\n", time.Now(), net.Self().ID[:16])
 		}
 	}()