SPOKANE, Wash. (AP) - Johnathan Williams had 18 points and 12 rebounds and No. 9 Gonzaga held off last-place Pepperdine 81-67 on Saturday night to remain in first place in the West Coast Conference.

Killian Tillie and Josh Perkins each scored 15 points for Gonzaga (25-4, 15-1 West Coast), which has won nine consecutive games since suffering its only league loss to No. 15 Saint Mary's.

Colbey Ross scored 21 points for Pepperdine (4-24, 1-15), which has lost seven straight.

Gonzaga has won 35 straight games against Pepperdine dating to 2002. The Waves have not won in Spokane since 1998.

Williams had his sixth consecutive double-double.

Gonzaga hit four 3-pointers during an early 20-6 run to take a 26-12 lead.

Gonzaga began missing and Pepperdine clawed back to trail just 34-28 late in the first.

The Zags led 39-32 at halftime, after holding the Waves to 41 percent shooting.

Three 3-pointers in the opening minutes of the second half lifted the Bulldogs to a 54-40 lead.

But the Waves came back and a basket by Trae Berhow cut Gonzaga's lead to 66-64 with 7:32 left. Killian Tillie hit a 3-pointer and Williams dunked to push Gonzaga's lead back to seven.

The Waves were scoreless for more than six minutes, missing seven shots, as the Zags built a 77-64 lead.

Feb 17, 2018; Spokane, WA, USA; National Anthem singer Andre Montgomery, center, joins Gonzaga for a pregame chant before a game against the Pepperdine Waves at McCarthey Athletic Center. Mandatory Credit: James Snook-USA TODAY Sports

BIG PICTURE

Pepperdine: The school announced earlier this week that Coach Marty Wilson, in his seventh season, will not return next year. Nine of the Waves have missed games with injuries this season. Colbey Ross leads all WCC freshmen in scoring at 14.3 points per game.

Gonzaga: The Bulldogs and No. 3 Villanova are the only teams in the nation that have six players averaging at least 10 points per game. Gonzaga has won at least 25 games for 11 consecutive seasons, trailing only Kansas' streak of 12. The Zags are seeking a 20th consecutive trip to the NCAA Tournament. This was senior night for Williams and Silas Melson.

UP NEXT

Pepperdine plays at No. 15 Saint Mary's next Thursday.

Gonzaga, which wrapped up its home season on Saturday, plays at San Diego next Thursday.