diff --git a/system_tests/full_challenge_mock_test.go b/system_tests/full_challenge_mock_test.go
index 82f57dd7ad..b7f484210f 100644
--- a/system_tests/full_challenge_mock_test.go
+++ b/system_tests/full_challenge_mock_test.go
@@ -7,7 +7,6 @@ package arbtest
 import "testing"
 
 func TestMockChallengeManagerAsserterIncorrect(t *testing.T) {
-	t.Parallel()
 	defaultWasmRootDir := ""
 	for i := int64(1); i <= makeBatch_MsgsPerBatch*3; i++ {
 		RunChallengeTest(t, false, true, i, defaultWasmRootDir)
@@ -15,7 +14,6 @@ func TestMockChallengeManagerAsserterIncorrect(t *testing.T) {
 }
 
 func TestMockChallengeManagerAsserterCorrect(t *testing.T) {
-	t.Parallel()
 	defaultWasmRootDir := ""
 	for i := int64(1); i <= makeBatch_MsgsPerBatch*3; i++ {
 		RunChallengeTest(t, true, true, i, defaultWasmRootDir)
diff --git a/system_tests/program_test.go b/system_tests/program_test.go
index 20bc873adc..5fa5db95c2 100644
--- a/system_tests/program_test.go
+++ b/system_tests/program_test.go
@@ -397,7 +397,6 @@ func storageTest(t *testing.T, jit bool) {
 }
 
 func TestProgramTransientStorage(t *testing.T) {
-	t.Parallel()
 	transientStorageTest(t, true)
 }