Dwayne Polee II scored 18 points off the bench as the Aztecs held off a late rally to defeat the Runnin' Rebels in the semifinals of the Mountain West Conference tournament in Las Vegas. Xavier Thames collected 17 points and six assists for top-seeded San Diego State (29-3), which will play New Mexico in Sunday’s title game. The Aztecs shot just 36.4 percent from the floor, but utilized their trademark defense to win their sixth straight game overall and reach the tourney championship game for the fifth time in six seasons. Deville Smith paced No. 4 seed UNLV (20-13) with 17 points and Bryce Dejean-Jones added 10. Khem Birch finished with 15 rebounds and five blocked shots for the Runnin' Rebels, which has lost five straight versus San Diego State in the conference tournament. Smith made UNLV's first 3-pointer of the game nearly four minutes into the second half to get his team within 33-31, but the Aztecs scored the next 12 points and held the Runnin' Rebels without a point for over seven minutes. Polee and Matt Shrigley hit consecutive 3-pointers in the burst while Polee added another to make it 48-33 with just over eight minutes left before UNLV made a charge. Smith hit another triple to cut the deficit down to 48-37 before he added a steal and score to make it a 10-point game with 3:22 left and nailed a third 3-pointer to slice San Diego State's advantage down to 54-45 with 1:42 remaining. Two more long range jumpers by Dejean-Jones got the Runnin' Rebels within five, but Polee made five free throws and a steal in the final minute to seal it. GAME NOTEBOOK: Thames had nine points in the first half as the Aztecs took a 29-24 lead into the break. ... San Diego State has won 118 straight games when leading with five minutes left. ... UNLV F Roscoe Smith had eight points while Shrigley and F Josh Davis scored six apiece for the Aztecs.