Gregory Darnell Williams appeals the district court’s denial of his 18 U.S.C. § 3582(c)(2) motion to reduce sentence seeking a reduction based on the retroactive amendments to the crack cocaine guidelines. The Government moves for summary affirmance, arguing that Williams was ineligible for relief under § 3582(c)(2) because he was sentenced not under the crack guidelines but as a career offender, pursuant to U.S.S.G. § 4B1.1.

Because Williams’s guideline range was not derived from the quantity of crack cocaine involved in the offense, but rather from his career offender status, the district court was correct in concluding that a sentencing reduction was not permitted. See § 3582(c)(2). Williams argues that the district court should have the authority pursuant to § 3582(c)(2) to reduce his term of imprisonment notwithstanding his status as a career offender in light of United States v. Booker, 543 U.S. 220, 125 S.Ct. 738, 160 L.Ed.2d 621 (2005). The argument is unavailing because “the concerns at issue in Booker do not apply in an 18 U.S.C. § 3582(c)(2) proceeding.” United States v. Doublin, 572 F.3d 235, 238 (5th Cir.), cert. denied, — U.S. —, 130 S.Ct. 517, — L.Ed.2d — (2009). Although the Guidelines must be treated as advisory in an original sentencing proceeding, Booker does not prevent Congress from incorporating a Guideline provision “as a means of defining and limiting a district court’s authority to reduce a sentence under § 3582(c).” Id. at 239 (internal quotation and citation omitted). Williams concedes that his argument is foreclosed by Doublin but seeks to preserve the argument for possible Supreme Court review.

Accordingly, the Government’s motion for summaiy affirmance is GRANTED, and the appeal is AFFIRMED. The Government’s alternative motion for an extension of time in which to file a brief is DENIED as unnecessary.