Fourth-ranked Gonzaga overcame a sluggish first half, fueled by guard Jordan Mathews' 20 points in the second half, in the Bulldogs' 82-50 win over Pacific in the quarterfinals of the West Coast Conference tournament Saturday in Las Vegas.

The Bulldogs, who improved to 30-1 overall, shot 67.9 percent (19 of 28) from the field in the second half after leading 27-25 at halftime.

Mathews, a graduate transfer from California, finished with a season-high 22 points. He made 6 of 7 shots from the field, including 4 of 5 from 3-point range in the second half. He also converted all four of his free-throw attempts.

"Jordan stepped up and made big-time shots," said forward Johnathan Williams, a Missouri transfer who finished with 11 points and six rebounds. "We need that from him every game."

Nigel Williams-Goss added 20 points, six rebounds and four assists for top-seeded Gonzaga, which advances to the WCC semifinal Monday night against No. 4 seed Santa Clara. The Broncos defeated No. 5 San Francisco 76-69 on Saturday.

T.J. Wallace had 20 points to lead Pacific, which finished its first season under coach Damon Stoudamire with an 11-22 record. The Tigers won their first WCC tournament game in program history with its win over Pepperdine Friday.

"I told my guys I'm proud of them for the way they fought as hard as they could in this game," said Stoudamire, who took over a program that had self-imposed sanctions that kept them out of last year's WCC tournament.

"These guys gave us the kind of effort we need to build this program."

Gonzaga struggled for most of the first half, making only 1 of 8 from 3-point range and committing nine turnovers. The Bulldogs had only four turnovers in the second half.

Wallace led Pacific with 10 points and Jack Williams had seven in the first half as they combined to make six of their 13 field-goal attempts.

The Tigers appeared hopeful trailing at halftime by only two points after Gonzaga swept the regular-season series convincingly with an 81-61 victory at Pacific and an 82-61 win in Spokane, Wash., on Feb. 18.

Gonzaga coach Mark Few acknowledged that his team took a while to get over the hangover of losing against BYU last week in Spokane, Wash., a loss that prevented the Bulldogs from staying unbeaten.

"Pacific appeared more comfortable than us in the first half," he said. "Our offense was bad in the first half and that affected our confidence. Thankfully, our rebounding and defense carried us long enough until our offense kicked into gear."

The Bulldogs pulled away to start the second half, going on a 14-2 run to open a 41-27 lead. Pacific made only 1 of 6 shots from the field in that stretch and Gonzaga converted on 5 of 6 attempts.

Gonzaga's run increased to 18-4 to open the half, culminating on two free throws by Zach Collins with 13:41 left in regulation. The Bulldogs led 45-29 at that point. Pacific did not draw closer.

The Bulldogs dominated the rebound battle 42-26 led by Przemek Karnowski's nine rebounds. Gonzaga outscored Pacific 32-14 in points in the paint.

The Tigers shot 30. 5 percent from the field, including only 25.8 percent in the second half. They did not record an assist in the second half after producing only four in the first half.

"We just started playing together like we have been doing," Williams said, explaining Gonzaga's second-half effort. "This is (the) first time shooting in this building (Orleans Arena). We just have to get used to it."

NOTES: Gonzaga G Josh Perkins left the game with 10:53 remaining with a sprained left ankle. He walked to the bench on his own power but did not return. Gonzaga coach Mark Few said the injury is worrisome but Perkins should be ready for Monday's game. ... Gonzaga is 49-15 in the WCC tournament with 15 titles and 22 finals appearances, including each of the last 19 seasons. The Bulldogs have a 12-game winning streak in the tournament after the win over Pacific. ... The Tigers recorded their first WCC tournament win, 89-84, over Pepperdine Friday. ... Since March 6, 2010, Gonzaga is 105-30 in road or neutral games. The Bulldogs' 77.8-win percentage on the road or neutral games tops the nation over that span. ... This year's WCC tournament marks the return of the Tigers to the WCC tournament after a self-imposed postseason ban kept them from participating last season. Pacific suffered first-round losses in each of its two previous appearances, an 81-64 loss to Santa Clara in 2014 and a 62-58 loss to San Francisco in 2015. ... Pacific F Jacob Lampkin, who scored 19 points in the first game against Gonzaga this season, was lost for the season with a fracture in his left foot on Feb. 2 against Saint Mary's.