No. 3 Alabama made a last-second decision to start Keelon Russell against Vanderbilt on Saturday after the quarterback looked better than anticipated in pregame warmups.

The Crimson Tide were expected to start Austin Mack against the Commodores after Russell was hampered throughout the week by lingering effects of an ankle injury. Mack took first-team reps in practice under the premise that he would be starting Saturday.

Russell, who has started every game this season and been one of the most impactful quarterbacks in the country, was expected to be available off the bench to let the injury heal, but he took equal reps with Mack in pregame warmups before the decision ultimately was made that he could play.

He suffered the ankle injury during the second half of last week's win at LSU. He got the ankle wrapped and played through the pain.

The sophomore from Texas has thrown for 2,263 yards with 18 touchdowns and five interceptions. He has rushed for 276 yards and five touchdowns. His 86.5 QBR is second only to Miami's Darian Mensah.

Russell beat out Mack for the starting job late in preseason camp.

Mack, a fourth-year player who followed coach Kalen DeBoer from Washington in 2025, has appeared in four games this season, completing 3 of 4 passes for 23 yards.

ESPN's Alex Scarborough contributed to this report.