San Diego State 73, Utah State 39

LAS VEGAS — Senior guard Xavier Thames had 15 points and seven assists as No. 8-ranked San Diego State crushed Utah State 73-39 in the quarterfinals of the Mountain West tournament on Thursday afternoon.

Forward Winston Shepard scored 13 points and forward Josh Davis added eight points, 13 rebounds and six steals for San Diego State, which held Utah State to a season-low point total and 29.3 percent shooting from the field.

The top-seeded Aztecs (28-3) will face the winner of Thursday’s quarterfinal game between UNLV (19-12) and Wyoming (18-13) in Friday night’s semifinals at 9 p.m. ET.

The 34-point margin of victory was the largest in Mountain West tournament history, topping Boise State’s 31-point (83-52) win over San Jose State on Wednesday night.

Any concerns that San Diego State might have a letdown after rallying for an emotional, court-storming 51-48 victory over New Mexico to win the Mountain West regular-season title last Saturday were quickly wiped away.

The Aztecs, who entered the game second in the nation in points allowed (57.2), jumped out to an 8-0 lead as Utah State missed its first shots from the field.

The eighth-seeded Aggies (18-14), who used a 16-3 run in the final 1:35 of regulation to pull out a 73-69 win over No. 9 seed Colorado State in Wednesday’s first round, closed to 14-8 on a jumper by center Jarred Shaw, but the Aztecs answered with a 17-3 run that was highlighted by back-to-back 3-pointers by Thames while building a 36-15 halftime lead.

San Diego State extended its lead to 34 points, 59-25, on a dunk by forward Skylar Spencer with 12:40 remaining. The Aggies, despite playing the final 10 minutes against San Diego State reserves, never got closer than 30 points the rest of the way.

Shaw finished with 14 points to lead Utah State.

NOTES: The 15 points were the fewest in a first half this season for Utah State, erasing the previous low of 22 scored at San Diego State on Feb. 18. … According to the San Diego Union-Tribune, San Diego State has now played 16 opponents during the last decade with 24 hours or less to prep for an opponent and had won all 16 of them, including a 86-80 victory over 14th-ranked Creighton in the Legacy Classic. … This is the third time the Aztecs have entered the Mountain West tournament as the No. 1 seed. San Diego State advanced to the championship game the previous two times, defeating Wyoming in overtime in 2006 to earn an automatic NCAA bid and losing to New Mexico in the 2012 title game. The Aztecs are trying to win their fifth tournament title, having also won it in 2002, 2010 and 2011.