Cutberto Arnoldo Casso appeals the sentence imposed following his guilty-plea conviction for possession with intent to distribute approximately 596 kilograms of marijuana. Casso argues that the district court erred under United States v. Booker, 543 U.S. 220, 125 S.Ct. 738, 160 L.Ed.2d 621 (2005), by sentencing him pursuant to a mandatory guidelines scheme.

Because Casso raises this argument for the first time on appeal, we review only for plain error. See United States v. Valenzuela-Quevedo, 407 F.3d 728, 732 (5th. Cir.), cert. denied, — U.S. —, 126 S.Ct. 267, 163 L.Ed.2d 240 (2005). Although the mandatory application of the Sentencing Guidelines constitutes error that is now clear in light of Booker, Casso has not shown that this error affected his substantial rights. See id.; United States v. Pennell, 409 F.3d 240, 245 (5th Cir. 2005). The fact that Casso was sentenced at the lowest end of the Guidelines does not indicate that his sentence would likely have been different under advisory Guidelines. See United States v. Bringier, 405 F.3d 310, 317-18 & n. 4. (5th Cir.), cert. denied, — U.S. —, 126 S.Ct. 264, 163 L.Ed.2d 238 (2005).

AFFIRMED.