Jason Kidd's 3-pointer with 40.3 seconds remaining in overtime led the Dallas Mavericks to a stunning 112-105 comeback victory over the host Oklahoma City Thunder in Game 4 of the NBA's Western Conference final Monday night.

After Dallas used a 17-2 run at the end of regulation to force OT, the teams traded baskets in the extra period until Kidd hit the go-ahead 3-pointer from the right corner. Russell Westbrook missed a layup on Oklahoma City's next possession, and Jason Terry hit a pair of free throws to put the game away.

Dirk Nowitzki scored 12 of his 40 points in the fourth quarter while Terry added 20 off the bench as the Mavericks moved to within a win of advancing to the NBA Finals. Dallas can wrap up the series with a home victory Wednesday night.

Kevin Durant had 29 points and 15 rebounds for the Thunder, who led by 15 points with less than five minutes remaining in the fourth quarter but frittered it all away. Westbrook added 19 points, eight rebounds and eight assists while Serge Ibaka had 18 points, 10 boards and five blocks.

With the Thunder leading 81-77 entering the fourth, a James Harden left-handed layup capped a 7-2 quarter-opening run and an Ibaka putback on his own miss put the Thunder up 92-81. Durant added a 3-pointer from the top of the arc with five minutes remaining to give Oklahoma City a 15-point edge.

Nowitzki led the Mavericks back, scoring nine straight points during the game-changing run that cut the deficit to two points with 38.6 seconds left. Thabo Sefolosha missed a 3-pointer at the other end and Nowitzki hit a pair of free throws with 6.4 seconds remaining to tie the game after he was fouled by Nick Collison.

Durant's long 3-point attempt was blocked by Shawn Marion and Dallas called a timeout with 1.7 seconds left. Dallas pressed for the winning shot, but Kidd's inbounds attempt was redirected by a Thunder player.