On direct appeal, appellant is challenging the voluntariness of his guilty plea without having first filed a petition with the lower court to withdraw that plea as required by Commonwealth v. Roberts, 237 Pa.Super. 336, 352 A.2d 140 (1975). However, a review of the record in this case shows that there were no warnings given to appellant of the consequences on appeal of this failure to file a petition to withdraw his guilty plea prior to challenging its validity.

Therefore, the judgment of sentence is vacated, and the case remanded for the filing of a petition nunc pro tunc as mandated by Commonwealth v. Johnson, 258 Pa.Super. 214, 392 A.2d 760 (1978).