The rest of the USC team was just as helpless as host Washington sunk 17 free throws without a miss over the final 17:40 to put the Trojans away, 65-57, on Wednesday night.
"I don't know what it was," USC senior Jio Fontan said after the Trojans lost for only the third time in a span of nine games. "Once they got to the free-throw line, they started to knock them down every time."
Scott Suggs scored 18 points and redshirt freshman Jernard Jarreau added a career-high 12 for the Huskies (17-13, 9-8 Pac-12). Six of Washington's made free throws came during a 13-2 spurt midway through the second half, which helped blow open a close game before Suggs and freshman point guard Andrew Andrews put the Trojans away down the stretch.
Andrews scored five of his seven points in the final 2:07. Suggs scored 11 of his 18 points after halftime, making 8 of 13 shots for the game. The fifth-year senior has averaged 19 points per game while making 21 of 33 shots over the Huskies' past three games.
Washington won its third straight game after losing eight of its previous 10.
Dedmon had 18 points for USC, which was leading 41-39 when he collected his fourth foul and came out of the game with 11:51 remaining. Washington went on to score nine unanswered points and never trailed again.
"He played a great game, and he definitely makes a difference on the floor," Washington's C.J. Wilcox said.
Dedmon returned with 6:10 remaining, just in time to watch Suggs hit a 3-pointer that gave the Huskies a 48-41 lead.
Washington made just 4 of 13 shots from 3-point range but made up for it with marksmanship at the free-throw line.
"It was all about confidence," said Jarreau, who made all of eight of his free-throw attempts in the second half.
Jarreau and Andrews combined for 19 points and 11 rebounds off the thin Washington bench, which played just three reserves.
"Coach (Lorenzo Romar) always tells us guys on the bench we have to step up, that we have to be ready when called," Jarreau said, "and that's what I've been doing."
USC's Fontan scored five points on 2-of-10 shooting while fighting through a sprained right wrist that had to be re-taped twice during the course of Wednesday's game. Fontan injured the wrist in a win over Arizona State on Saturday.
"It was real tough," Fontan said of playing with the injury to his shooting wrist. "I couldn't really shoot the ball, and I couldn't drive to my right. They did a good job of catching on to it in the second half, and they made adjustments."
Fontan had an effect on the defensive end of the floor, holding Wilcox to 11 points on 2-of-9 shooting. Wilcox has averaged 10 points per game more than seven below his season average while making just 5 of 16 shots in two games against USC.
Asked why he refused to sit out with the injury, Fontan said: "We've been on a roll. I didn't want to not be a part of whatever outcome whether we won or lost the game."
The Trojans (14-16, 9-8) shot just 37.5 percent from the field for the game.
One of the biggest ovations of the night came when Seattle Seahawks coach Pete Carroll was introduced during a timeout. Carroll, who coached at USC for nine years, was sitting behind the Trojans' bench Wednesday.
Washington's Andrews had eight rebounds, including five on the offensive end to continually keep possessions alive in the second half. The Huskies outrebounded USC 48-29.
"We played with energy," Romar said. "There are a lot of good things that happen as a byproduct of playing with energy."