CORVALLIS — Oregon State managed its first lead of the weekend but seventh-ranked Arizona State came back to beat the 16th-ranked Beavers 8-1 in Pacific-10 baseball Sunday afternoon at Goss Stadium at Coleman Field.

CORVALLIS — Oregon State managed its first lead of the weekend but seventh-ranked Arizona State came back to beat the 16th-ranked Beavers 8-1 in Pacific-10 baseball Sunday afternoon at Goss Stadium at Coleman Field.

OSU (36-16 overall, 8-13 Pacific-10) saw the Sun Devils (41-12, 17-4) clinch at least a tie for the Pacific-10 championship that the Beavers had won the past two seasons.

OSU now finishes its regular season with a series at UCLA next weekend beginning Friday.

"We need to go down there and win the series if we're going to play at the end of the season," OSU head coach Pat Casey said of the Beavers needing to build their case for a third straight postseason appearance and a chance to defend their 2006 national championship.

On Sunday, ASU lefthander Brian Flores threw a one-hitter at the Beavers, allowing just a second-inning single up the middle by Braden Wells. Flores walked three and struck out eight as he improved his record to 9-1 this season.

Oregon State limited Arizona State to an average of five runs per game in the series, half of what the Sun Devils — the nation's highest-scoring team going into the weekend — had been averaging. But OSU was limited to four runs in the series and had three hits in the final two games.

"I thought we played good baseball in the first two games of the series, but I don't think we played very well today," Casey said. "I don't think there was that sense of urgency you're looking for when your backs are to the wall."

The Beavers — the national leaders in fielding percentage entering the week — committed a season-high six errors in the contest; OSU hadn't committed an error in its last six games and had committed a total of five errors in their last 18 games.

The start of the game was delayed 48 minutes by rain.

Prior to the contest, OSU honored the seniors playing their final regular season home game — pitcher Greg Keim, outfielder Lissman, pitcher Anton Maxwell, pitcher Jake McCormick and outfielder Scott Santschi.