Washington State’s 3-point sharpshooter was quiet for much of the night, but when it counted most, Jabe Mullins delivered.

The junior guard drained a go-ahead triple with 3 seconds remaining, lifting WSU to a 66-64 victory over George Washington University on Thursday during the first round of the Diamond Head Classic at Stan Sheriff Center in Honolulu.

“He’s just a weapon out there,” WSU coach Kyle Smith said of Mullins. “You can’t leave him open.”

George Washington guard E.J. Clark hit 1 of 2 free-throw attempts to put the Colonials on top 64-63 with 15 seconds on the clock. WSU guard TJ Bamba nearly lost the ball on the ensuing possession but plucked it off the floor between two diving defenders and tossed a pass to Mullins, who had a clean look from the wing.

The Colonials missed a long 3-point try at the buzzer.

“They left Jabe open and he really buried a big shot,” Smith said.

Mullins finished with eight points (2 of 4 on 3s) and four assists coming off a 16-point effort against Baylor last week in his return to the court after missing four games with an injury. The Saint Mary’s transfer is shooting 52.4% from downtown.

The Cougars (5-6) snapped a two-game skid. They were competitive in both games – against unbeaten UNLV and 11th-ranked Baylor – but ran out of gas late.

In another back-and-forth affair, WSU pulled through in crunch time to open its stay at the holiday tournament, and the Cougars’ clutch finish “should give us confidence in (close) games,” Smith said.

“We hadn’t been able to break through,” he said. “They were just locked in (late against the Colonials).”

The Cougars stayed in front throughout the first half and for the first 11 minutes of the second half but couldn’t separate from the Colonials (6-5).

The teams traded the lead eight times over the final 7 minutes . WSU led by as many as eight points midway through the first half but managed only seven points the last 10:40 . The Cougars went up by seven points on two occasions in the second half, but George Washington capitalized on WSU droughts and stayed within striking distance.

“We couldn’t quite get stops and couldn’t quite put together enough good possessions,” Smith said. “But we were able to battle back and get a win. Knowing we can control the game most of the way, lose the lead and come back and win, that should give us (confidence).”

WSU’s Mouhamed Gueye paced all players with 21 points, shooting 9 of 14 from the field. He added 10 rebounds. Gueye was helped off the court at the 17:46 mark of the second half after slipping and bending his ankle, but the 6-foot-11 sophomore returned following a brief check-up on the sideline and gave the Cougars a boost, scoring 10 points in the final 15 minutes.

“He was tremendous, really from the get-go,” Smith said of Gueye, who had 11 points after seven minutes of game time. “He was aggressive on the glass … tenacious. He’s only going to keep getting better. (After) he tweaked his ankle, I was proud of how he kept competing.”

Bamba added seven rebounds and 17 points on 5-of-11 shooting from the field. WSU forward DJ Rodman had eight boards and four assists.

WSU shot 42% as a team and went 7 for 26 (26.9%) on 3-pointers. The Cougars outrebounded the Colonials 39-26, including a 13-4 advantage on the offensive glass. WSU committed 14 turnovers and shot 11 of 18 from the foul line.

Guard Brendan Adams led the Colonials with 17 points. Guard James Bishop IV, who entered the game ranked No. 7 nationally with 22.2 points per game, was limited to 10 points on 5-of-14 shooting . George Washington shot 49% and hit 3 of 18 on 3-pointers.

Veteran forward Andrej Jakimovski returned to the lineup after missing the Cougars’ first 10 games of the season with a foot injury. He had two points and two rebounds in 13 minutes.

Forward Mael Hamon-Crespin was not with the team Thursday and is no longer listed on WSU’s roster.

“He’s got some personal thing that he’s tending to,” Smith said of Hamon-Crespin, who is averaging three points and 0.6 rebounds across eight appearances. “I’ll talk to him and get a definite on what’s going on, but he needs a break right now.”

The Cougars advance to the semifinal round, which will tip off at either 7 p.m. or 9 p.m. Friday. WSU will face the winner of Hawaii and Pepperdine, which was still in progress at press time.