Ramon Ernesto Medina Limas (“Medina”) appeals his guilty plea conviction and sentence for illegally reentering the United States after having been deported and after having been convicted of a felony, in violation of 8 U.S.C. § 1326(a) and (b). For the first time on appeal, Medina argues that his 57-month prison sentence violates United States v. Booker, — U.S. -, 125 S.Ct. 738, 160 L.Ed.2d 621 (2005), insofar as he was sentenced under the formerly mandatory Sentencing Guideline regime.

Medina concedes that, under this court’s precedent, his Booker claim fails because he cannot show that the alleged error affected his substantial rights. See United States v. Valenzuela-Quevedo, 407 F.3d 728, 733 (5th Cir.), cert. denied, — U.S.-, 126 S.Ct. 267, — L.Ed.2d-(2005); United States v. Mares, 402 F.3d 511, 521 (5th Cir.), cert. denied, — U.S. -, 126 S.Ct. 43, — L.Ed.2d - (2005). To the extent that Medina contends that application of the mandatory Guideline regime was a “structural” error that is not susceptible to plain-error analysis, or alternatively that plain-error prejudice should be presumed, we have rejected such arguments. See United States v. Martinez-Lugo, 411 F.3d 597, 601 (5th Cir. 2005), cert. denied, — U.S.-, 126 S.Ct. 464, — L.Ed.2d-(2005).

AFFIRMED.