OMAHA, Neb. — Chad Flack hit a leadoff triple and rumbled home to score the go-ahead run on a passed ball in the eighth inning, leading North Carolina to a 4-3 victory over Oregon State in the opening game of the College World Series championship round Saturday night.

The Tar Heels (54-13) need to beat the Beavers (48-16) once more in the best-of-three series for their first national title in baseball.

With the game tied at 3 in the eighth, Flack hit a hard liner into the right-field corner and slid into third with a triple. With Jay Cox at the plate, reliever Joe Paterson threw an inside pitch that tipped off catcher Mitch Canham's mitt and rolled to the backstop.

Flack, 6-foot-3 and 215 pounds, took off for home as Canham recovered the ball and tossed it to Paterson at the plate — but Flack slid headfirst ahead of the tag.

In the ninth, reliever Jonathan Hovis (8-2) issued a leadoff walk to Chris Kunda, but Andrew Carignan came on after Canham's sacrifice and struck out Darwin Barney and John Wallace for his 15th save.

The Tar Heels are trying to become the first Atlantic Coast Conference team to win the College World Series since Wake Forest in 1955. Paterson (1-1), who came on in relief of starter Dallas Buck, took the loss for Oregon State.

Oregon State took a 3-2 lead in the sixth on Cole Gillespie's two-run homer off starter Andrew Miller. Wallace hit a leadoff single and moved to third when the lanky lefty's pickoff attempt went past Flack at first base and into the Beavers' bullpen in right field.

Gillespie reached out and hit a 1-2 pitch from Miller over the right-field wall — just before drenching rains delayed the game for 1 hour and 11 minutes.

When play resumed, Matt Danford came out for North Carolina in relief of Miller and walked two batters before getting out of the inning.

Buck came out for the Beavers in the sixth, and got into trouble by giving up consecutive singles to Flack and Cox. He got Tim Federowicz to ground into a double play, but Seth Williams followed with an RBI to tie it at 3.

Buck walked off the mound, slapped his glove in frustration and yelled at himself before pitching coach Dan Spencer came out to calm the right-hander. Buck regained his composure and got Benji Johnson to ground out.

The Tar Heels scored twice with two outs in the opening inning. Josh Horton drew a walk and went to third on Flack's single past a diving Shea McFeely at third base. Cox followed with a run-scoring single, and Federowicz blooped a single in front of center fielder Tyler Graham.

Oregon State got on the scoreboard against Miller in the third, thanks in part to an overly aggressive North Carolina fan.