SAN JUAN, Puerto Rico (AP) -- Casey Mitchell could hardly believe his luck. One defender flailed at the ball on a steal attempt and a botched defensive switch left him all alone on the wing with a clean look ahead.
"I took my time, took a deep breath and let it go," Mitchell said.
He let the shot fly, and sent West Virginia off to a title game.
Mitchell hit the winning 3-pointer with 3.8 seconds left, finishing with a career-high 31 points to lift the Mountaineers past Vanderbilt 74-71 Friday and into the Puerto Rico Tip-Off championship.
The Commodores (2-1) will play North Carolina for third place in the tournament Sunday at 4:30 p.m. CT on ESPN2.
Mitchell and Vanderbilt's John Jenkins hit all the big shots as the teams went basket-for-basket over the tense final minutes. Mitchell came out on top when he made his sixth 3 of the game from the wing on a pass from Truck Bryant.
"They switched the D the last couple of seconds and my eyes lit up," Mitchell said. "I knew I'd get a wide-open shot."
Jenkins scored 27 points and hit the tying 3 with 1:58 left after the Commodores trailed almost the entire way.
Kevin Jones had 12 points and 11 rebounds for West Virginia.
Rod Odom, who missed a last-chance shot as time expired, had 11 points for Vanderbilt.
The wild finish even included two Vanderbilt fans getting tossed from the stands for berating the refs.
Jenkins rallied the Commodores from a 14-point hole and tied the game. He was fouled on a 3-point attempt and made all three from the free-throw line for the second time in the game to cut the lead to 68-65 with 2:57 left. He tied it at 68 on a 3 that sent him jumping and bumping with teammates going into a timeout.
The Commodores could never take the lead, tying it one final time at 71 with 32.6 seconds left.
Mitchell worked his way wide open when Vanderbilt switched to a 2-3 zone during the possession and had an open look at the basket for the winner.
"We should have had him covered on that last play," Vanderbilt coach Kevin Stallings said. "There was no reason for him to have gotten that shot on the last play. We just missed coverage and didn't do what we were coached to do.
"But he still had to make the shot and he did."
It got worse on the final shot, when it fell to Odom instead of Jenkins for a chance at overtime.
"I had a play that would have worked," Stallings said. "I don't know if we would have made the shot or not, but I got talked out of it. That's my fault."
Mitchell hit three 3-pointers during a 12-1 run earlier in the second half that gave West Virginia some breathing room. It was needed once Jenkins got hot down the stretch.
The Commodores blew a chance to seize control on a missed fastbreak layup on one possession, then missed three shots on another. Jenkins bailed out the Commodores with a 3 that pulled them to 50-45.
Brad Tinsley made the second of two free throws to tie the game at 52 with 9:54 left. Odom kept the score tied at 54 and the Mountaineers took off in a frenzy, scoring eight straight points in 50 seconds.
Mitchell went wild on the final 3 in that spurt that put them up 63-54, waving his hands in excitement to a crowd colored with West Virginia yellow.
"We've got a lot of confidence in Casey," West Virginia coach Bob Huggins said. "It's a harder thing to do than what you think."
In the first half, West Virginia went 18 for 24 from the free-throw line and Vanderbilt was 6 of 7. That made all the difference as the teams were even (12 for 29) in field goal shooting.