LSU received 59 out of 60 first-place votes after beating the Crimson Tide 9-6 in overtime in Tuscaloosa, Ala., on Saturday night.
Oklahoma State moved up one spot after a wild 52-45 victory against Kansas State and Stanford also moved up a spot to third.
Alabama slipped two spots Sunday. Boise State remained No. 5 with one first-place vote.
The rest of the top 10 was No. 6 Oregon, followed by Oklahoma, Arkansas, Clemson and Virginia Tech.