Mathews' teammate, Nick Rakocevic, watched nervously, thinking the shot looked good from his vantage point.
It wasn't, and Southern California escaped with a 69-64 victory over Stanford on Wednesday night to move into a virtual tie with Arizona atop the Pac-12, although the Trojans (7-2) trail the idle Wildcats (6-1) by percentage points.
"My heart stopped a little bit," Rakocevic said.
Mathews added, "I turned around because I didn't want to look."
They couldn't be blamed for having flashbacks to USC's 77-76 loss on a shot from beyond half-court at Stanford on Jan. 7.
But the worries were brief, and the Trojans continued their best start in league play since 2002, when they were also 7-2.
"Our confidence is through the roof right now," said Rakocevic, who had nine points and eight rebounds.
Mathews scored 18 points and Chimezie Metu added 12 points and 10 rebounds for the Trojans (16-6), who have won five in a row and 10 of 12.
"Our defensive perspective has changed a lot over the last few weeks," Rakocevic said. "We emphasizing defense a lot more and we're doing a good job of executing."
"We weren't in the flow of the game," Stanford coach Jerod Haase said. "It was kind of `Hey, let's go out there and see how it goes and figure things out.' It can't be that way."
Humphrey hit a 3-pointer and Davis made two free throws that got Stanford to 66-64.
Jordan McLaughlin had a rocky time in the final seconds. He missed a 3-pointer and then missed 3 of 4 free throws that left USC clinging to a 67-64 lead.
After Davis' miss, USC regained possession and Elijah Stewart caught a long pass near midcourt and cruised in for a game-ending dunk.
Trailing by 15 points at the break, Stanford regrouped to start the second half with a 15-7 spurt. Pickens made 6 of 6 free throws and Travis added five points to cut the Cardinal's deficit to 48-41.
The Trojans took control with a 12-0 run that turned a four-point lead into a 15-point advantage in the first half. Rakocevic had five points, one of four players to score in the spurt that extended USC's lead to 28-12.
USC led 41-26 at halftime after holding Stanford to 36 percent shooting.
With USC ahead by three, McLaughlin missed a free throw, but immediately made up for it by swiping the ball from Davis. "He's got lightning-quick first two steps," USC coach Andy Enfield said of his guard. "That was just great anticipation."
The Trojans are forcing 16 turnovers a game, and that's how many Stanford had. USC committed just seven turnovers, although McLaughlin had two and Metu had one in the final 7:51. USC has forced 131 turnovers and made 64 steals in the last eight games.
Stanford: The Cardinal shot 44 percent, ending USC's run of holding its previous opponents to 43 percent or less.
USC: The Trojans led the entire game and were up by 10 points with 5:12 remaining before surviving their own miscues to hang on.
Stanford: Visits UCLA on Saturday. The Cardinal needed a buzzer-beater in double overtime to earn a 107-99 victory three weeks ago.
USC: Hosts California on Sunday, a team the Trojans beat by 18 points on Jan 4.
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Villanova's reign ends in 'ugly game' vs. Purdue
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Edwards sets Purdue record in 42-point performance
Carsen Edwards hits nine 3-pointers, a Purdue record, and scores a career-high 42 points in the 87-61 win over Villanova.
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