diff --git a/internal/checks/latency_test.go b/internal/checks/latency_test.go
index 1b35ed38..ee8cad98 100644
--- a/internal/checks/latency_test.go
+++ b/internal/checks/latency_test.go
@@ -120,6 +120,8 @@ func Test_isErrorMatches_True(t *testing.T) {
 	Assert.True(isErrorMatches("a", []string{"a", "b"}))
 	Assert.True(isErrorMatches("aa", []string{"a", "b"}))
 	Assert.True(isErrorMatches("some error", []string{"a", "err"}))
+	Assert.True(isErrorMatches("error string", []string{"error string"}))
+	Assert.True(isErrorMatches("prefix error string suffix", []string{"error string"}))
 
 	Assert.True(isErrorMatches("aba", []string{"ab"}))
 	Assert.True(isErrorMatches("aba", []string{"ba"}))