diff --git a/notifier/github/commits.go b/notifier/github/commits.go
index c8c2fad..13bdc29 100644
--- a/notifier/github/commits.go
+++ b/notifier/github/commits.go
@@ -37,8 +37,8 @@ func (g *CommitsService) lastOne(commits []string, revision string) (string, err
 	if revision == "" {
 		return "", errors.New("no revision specified")
 	}
-	if len(commits) == 0 {
-		return "", errors.New("no commits")
+	if len(commits) < 2 {
+		return "", errors.New("not enough commits")
 	}
 	// e.g.
 	// a0ce5bf 2018/04/05 20:50:01 (HEAD -> master, origin/master)
diff --git a/notifier/github/commits_test.go b/notifier/github/commits_test.go
index 7035367..87455a8 100644
--- a/notifier/github/commits_test.go
+++ b/notifier/github/commits_test.go
@@ -70,6 +70,15 @@ func TestCommitsLastOne(t *testing.T) {
 			lastRev:  "",
 			ok:       false,
 		},
+		{
+			// one commit
+			commits: []string{
+				"04e0917e448b662c2b16330fad50e97af16ff27a",
+			},
+			revision: "04e0917e448b662c2b16330fad50e97af16ff27a",
+			lastRev:  "",
+			ok:       false,
+		},
 	}
 
 	for _, testCase := range testCases {
diff --git a/notifier/gitlab/commits.go b/notifier/gitlab/commits.go
index 41476f0..bf33d77 100644
--- a/notifier/gitlab/commits.go
+++ b/notifier/gitlab/commits.go
@@ -33,8 +33,8 @@ func (g *CommitsService) lastOne(commits []string, revision string) (string, err
 	if revision == "" {
 		return "", errors.New("no revision specified")
 	}
-	if len(commits) == 0 {
-		return "", errors.New("no commits")
+	if len(commits) < 2 {
+		return "", errors.New("not enough commits")
 	}
 
 	return commits[1], nil
diff --git a/notifier/gitlab/commits_test.go b/notifier/gitlab/commits_test.go
index 7395004..0cbe947 100644
--- a/notifier/gitlab/commits_test.go
+++ b/notifier/gitlab/commits_test.go
@@ -70,6 +70,15 @@ func TestCommitsLastOne(t *testing.T) {
 			lastRev:  "",
 			ok:       false,
 		},
+		{
+			// one commit
+			commits: []string{
+				"04e0917e448b662c2b16330fad50e97af16ff27a",
+			},
+			revision: "04e0917e448b662c2b16330fad50e97af16ff27a",
+			lastRev:  "",
+			ok:       false,
+		},
 	}
 
 	for _, testCase := range testCases {