MORAGA, Calif. -- An undefeated regular season became a very realistic goal for top-ranked Gonzaga on Saturday night.

The Bulldogs got past what appeared to be their biggest remaining obstacle in pursuit of perfection by beating No. 20 Saint Mary's 74-64 in a pivotal West Coast Conference game at jam-packed 3,500-seat McKeon Pavilion.

Gonzaga (26-0, 14-0 WCC) has a two-game conference lead over Saint Mary's with just four games left, putting the Bulldogs on target to claim at least a share of the regular-season WCC championship for the fifth straight year and for the 16th time in the past 17 seasons.

If the Bulldogs win those four games -- against San Francisco, Pacific, San Diego and BYU -- they would then need to win three games in the WCC tournament to enter the NCAA Tournament with a perfect record. They would become the third team in the past four seasons to do it, joining Wichita State in 2014 and Kentucky in 2015. Neither of those teams reached the NCAA championship game.

Saint Mary's (22-3, 12-2) had the loud support of its home crowd but had its seven-game win streak halted by a Gonzaga team that bullied the Gaels in the paint.

Przemek Karnowski, the Bulldogs' 7-foot-1, 300-pound center, scored 10 points in the first four minutes of the game to put the Bulldogs in control early. He finished with 19 points on 9-of-13 shooting from the field despite being slowed by a sprained ankle suffered about five minutes before halftime.

Karnowski had scored just nine points in Gonzaga's 79-56 victory over Saint Mary's on Jan. 14, but he was the dominant player this time.

"There's not many like him in college basketball," Gonzaga coach Mark Few said. "He's big, he can pass. And on the other end he's a mountain of a man inside."

"He's a force," said Gaels 6-11 center Jock Landale, who scored 24 points but could not handle Karnowski defensively, "and he has a nice repertoire of shots."

Guard Nigel Williams-Goss, the Bulldogs' leading scorer this season, had 14 points but played a secondary role this time.

"He's phenomenal," Williams-Goss said of Karnowski. "He's our anchor. He's one of the best if not the best center in the country."

Karnowski got assistance in the paint from 6-9 Johnathan Williams, who made 7 of 9 shots from the floor while scoring 17 points for Gonzaga, which shot 55.3 percent from the field for the game.

"They had a field day on us in the post," Saint Mary's coach Randy Bennett said. "We let them catch the ball in the post too easy. And then when we let them get it, we didn't put enough on them."

The Gaels made several runs at Gonzaga, but the Bulldogs responded each time,

Karnowski dominated the first half, which ended with Gonzaga leading 40-31. Karnowski scored 15 first-half points on 7-of-8 shooting from the floor, and he rebounded his only miss and turned it into a three-point play.

Gonzaga led by 12 points early in the second half and by 10 with 16:22 remaining when Landale was forced to the bench with his fourth foul.

The Gaels trimmed the deficit to 49-44 when Calvin Hermanson hit a 3-point shot with 13:30 left, but Gonzaga quickly increased the margin to 13 points.

Saint Mary's got the deficit down to eight again but could get no closer.

The Gaels shot just 37.9 percent from the floor in the second half against a Gonzaga defense that began the day ranked second nationally in field-goal percentage defense at 37.0 percent.

"Defense needs to travel," Karnowski said, "and it's been traveling with us."

It was left to Bennett, who has been facing Gonzaga for 16 years at Saint Mary's, to answer whether this is the best Gonzaga team he has faced.

"I think so," he said. "That team is good. I don't know what their holes are. People say they are this or that, but nobody has come close."

None of Gonzaga's last 18 wins has been closer than 10 points.

NOTES: The last time a No. 1 team played a game on the Saint Mary's campus was Feb. 16, 1955, when top-ranked San Francisco, led by Bill Russell, defeated the Gaels about a month before the Dons won their first national championship. ... Saturday was the fourth time that Saint Mary's and Gonzaga met when both teams were ranked. ... Gonzaga had won 11 of the last 13 games against Saint Mary's. Saint Mary's won both regular-season games between the teams last season, but Gonzaga won at matchup in the conference tournament to land the West Coast Conference's only NCAA tournament berth. Saint Mary's was relegated to the NIT last season despite a 27-5 record. ... Gonzaga shot 64.7 percent from the field when it beat Saint Mary's 79-56 in the first meeting this season on Jan. 14 in Spokane, Wash.