What is the test for a motion to challenge the validity of a defendant's guilty plea on the grounds of ineffective assistance of counsel?

Defendant has also alleged ineffective assistance of counsel. A defendant seeking to challenge the validity of their guilty pleas on the ground of ineffective assistance of counsel must demonstrate that his counsel's performance was deficient and that this deficient performance prejudiced him. In order to establish prejudice, Defendant "must show that there is a reasonable probability that, but for counsel's unprofessional errors, the result of the proceeding would have been different." Strickland v. Washington, 466 U.S. 668, 694 (1984). "A reasonable probability is a probability sufficient to undermine confidence in the outcome." Id. However, there is a "strong presumption that counsel's conduct falls within a wide range of acceptable professional assistance." Id. at 689.