EUGENE — Junior left-hander David Peterson ended Oregon's five-game losing streak and bounced back from a rare subpar outing in emphatic fashion Friday, striking out 20 batters in a four-hit shutout of Arizona State, 2-0, before 1,296 fans in PK Park.

"I felt like myself again," said Peterson (9-2), a midseason national player of the year candidate who suffered his second loss while pitching through illness a week earlier. "I was sick last week, but today when I got my lift in, and got my rest earlier, I felt like me again. I was pretty anxious in the bullpen, but once I got out there I was pretty comfortable."

Peterson set the tone from the outset, striking out the side in the top of the first. He did so again in the fifth inning, and capped the game by striking out three straight in the ninth following a leadoff double. Peterson's 20 strikeouts matched the program record by an Oregon team in a single game, much less a single pitcher, and matched the NCAA single-game leader entering the start of play Friday, J.P. Sears of The Citadel.

"I felt like I had it," said Peterson, who also pitched around his own error in the second, his only walk in the fourth and a one-out triple in the eighth. "I felt like I could throw any pitch at any time."

The Ducks (24-13, 7-9 Pac-12) gave Peterson the only offense he needed in the fourth. Spencer Steer led off with a walk, and Gabe Matthews put runners at the corners with a single. The third straight true freshman of the inning, Matthew Dyer, dropped a bunt up the first-base line that scored Steer, with Dyer also reaching when nobody covered first for the Sun Devils (18-21, 5-11). Matthews later scored on an error for a 2-0 lead.

Peterson did the rest, striking out double-digit batters for the fifth time this spring, one shy of the UO single-season record set by Tyler Anderson in 2011. Based on statistics at the start of play nationally Friday, Peterson has two of the five top strikeout totals in the nation this season, having struck out 17 against Mississippi State on March 3.

And more importantly to the Ducks, Peterson helped end their losing streak, sparking Oregon's postseason hopes.

"Just in general, it's always my job to start the week off right," Peterson said. "We came out with good energy as a team, and whatever came our way, we were going to overcome it."