PORTLAND, Ore. -- Barret Peery wanted to see what he would get from his team Sunday, two days after a difficult two-point loss to Butler at the PK80 Invitational.
Portland State's coach got a squad that didn't go away after falling behind by double digits in the first half.
The Vikings kept up their trapping defensive pressure and eventually turned the game in their favor.
Portland State forced 28 Cardinal turnovers and got 22 points and seven rebounds from Deontae North on Sunday night in an 87-78 win at Veterans Memorial Coliseum.
"We were relentless. Our guys didn't stop," said Peery, whose team outscored Stanford (3-5), a physically bigger team, 52-34 in the second half.
Bryce Canda added 17 points for the hometown Vikings (5-2), who erased a nine-point halftime deficit.
Reid Travis had 28 points and 14 rebounds for Stanford (3-5).
Portland State trailed by as many as 14 in the first half.
Mayhew hit a 3-pointer that made it 58-57, Portland State's first lead since the opening minutes. The Vikings led by as many as six points, saw the Cardinal close within three, then went ahead 72-62 after a 7-0 run capped by Holland Woods' steal and basket with 4:43 remaining.
Portland State led by as many as 17 in the closing minutes.
The Vikings' defense kept the Cardinal guessing. Stanford, which had 15 turnovers in the second half, couldn't depend on seeing a set defense from Portland State.
"For us, it's different when guys are running, trapping out of the blue. You really don't know where it's coming from," Travis said, adding that his team got into a "rat race" and started playing Portland State's style after halftime.
North said Perry told the players at halftime to "keep coming" with the defensive pressure and that it would eventually pay off.
"We saw that," North said. "They started to turn the ball over multiple times in a row, and it just helped us get our momentum. We started making shots, started making plays."
Woods added 13 points for the Vikings, all in the second half. North, who made 9 of 10 free throws and had three steals, scored 14 of his 22 points after halftime.
Robert Cartwright had 19 points for Stanford.
Both Stanford and Portland State were in the Motion Bracket of the 16-team tournament. The field included No. 1 Duke and No. 4 Michigan State.
The three-day event, dubbed the PK80, celebrated Nike co-founder Phil Knight's 80th birthday.
Stanford fell 79-71 to Ohio State on Friday. The Cardinal opened the tournament on Thanksgiving day with a 108-87 loss to No. 7 Florida.
Portland State had the misfortune of playing No. 1 Duke in the tournament opener. The Vikings hung tough with the Blue Devils for the first half of the game, trailing just 49-45 at the break, but ultimately lost 99-81.
Portland State rallied but fell short in its second game, a 71-69 loss to Butler.
Stanford is 2-1 all-time against Portland State, winning the most recent meeting 83-64 on Nov. 29, 2009.
Portland State: The Vikings were averaging 11 3-pointers a game, tops in the Big Sky Conference. Portland State had just 19 total turnovers in the first two games of the tournament.
Stanford: The PK80 wraps up a span where Stanford faced three teams from Power Five conferences. The Cardinal opened the week with a loss to defending NCAA champion North Carolina on Monday. ... Travis led Stanford with an average of 18.5 points in the opening two games of the tournament.
The Vikings play Portland Bible at Lewis and Clark College next Saturday.
Stanford hosts Montana on Wednesday.