BERKELEY, Calif. — From his perch in room 763 inside the Memorial Stadium press box, Pete Kwiatkowski was fuming.

Washington’s defensive coordinator watched California’s offense march 79 yards in nine plays, settling all too easily inside the UW 1-yard line, maybe an inch from the goal line. The Bears’ high-powered offense was about to take an early lead in an important early-season showcase for both teams.

The Huskies’ fortunes on this day, and perhaps in this season, flipped in an instant.

Linebacker Shaq Thompson returned a fumble 100 yards for a UW touchdown, a 14-point swing from which Cal could never recover in the Huskies’ 31-7 victory Saturday.

“We knew we had to come in and make a statement, and we definitely did that,” senior receiver DiAndre Campbell said. “We did what we were supposed to do.”

Thompson’s fumble return highlighted a two-week about-face following the Huskies’ Pac-12 opening loss to Stanford. After their only bye week of the season, the Huskies got significantly improved play from quarterback Cyler Miles on Saturday and won the battle at the line of scrimmage on both sides of the ball, giving the Huskies (5-1, 1-1 Pac-12) some optimism heading into their rivalry game at Oregon this week.

“To come in here and hold them to seven points — I didn’t think that would happen,” UW coach Chris Petersen said.

Cal came into the game averaging 50 points per game, second in the nation, and some were starting to mention sophomore quarterback Jared Goff as a darkhorse Heisman Trophy candidate.

It was Goff’s fumble at the goal line, on a quarterback sneak, that led to Thompson’s recovery and return.

“It just popped into my hands — magnet,” Thompson said.

Goff had four of Cal’s five fumbles, leading to three turnovers for the Huskies. UW’s plus-14 turnover margin is the best in the country.

“Every game, they scored 50-plus points (on average), so we knew we had to hold them, and that’s what we did,” Thompson said.

UW senior defensive end Hau’oli Kikaha had three of UW’s four sacks against a Cal offense that had given up just eight sacks in its first five games.

For much of the game, the Huskies were able to put pressure on Goff while rushing just four defensive linemen, allowing them to drop an extra defender into coverage against the Bears’ four- and five-receiver sets. Kwiatkowski said he called just two blitzes in the first half and two more in the second half when UW’s regular defense was still on the field.

A month ago, after the Huskies allowed 52 points in a too-close victory over Eastern Washington at home, the natural question was whether UW’s thin and inexperienced secondary would be able to hold up against the prolific passing offenses in the Pac-12.

“We’ve got prideful guys, and they want to get better and they are getting better,” Kwiatkowski said. “They play hard and they believe, and that’s all you can ask.”

Thompson, a Sacramento native who had made a verbal commitment to Cal out of high school before backing out, had 25 family and friends in the stands. They watched him have the longest fumble return in UW history, and just the fourth 100-yard play in program history.

“He’s just got the football ‘it’ factor,” Petersen said.

Said Kikaha: “Every game he does something amazing — so look out for the Heisman right there.”

It’s the sort of uncanny play that has become common for Thompson, who has four defensive touchdowns in six games this season, plus a fifth touchdown on offense. After scoring, Thompson flipped the ball out of the end zone and saluted UW fans sitting beyond the south end zone. He was then tackled by a mob of teammates.

A couple hours later, the celebration extended into a rumbling UW locker room after a resounding win.

Adam Jude: 206-464-2364 or ajude@seattletimes.com. On Twitter @a_jude

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