OMAHA—The lone regional No. 2 seed at the College World Series knocked off the No. 1 national seed in the first game of Monday's weather-induced tripleheader.

Clemson jumped on an erratic Arizona State starter Seth Blair for two runs in the second and padded its lead with three more in the fifth, en route to a 6-3 win against the Sun Devils. Tigers lefthander Casey Harman earned the win, allowing just three runs over six solid innings before handing off to righty Alex Frederick, who worked three scoreless, one-hit innings for his third save.

Clemson rapped out 14 hits—all singles—in the game and drew five walks against Blair. The ASU bullpen kept the Tigers scoreless over the final three innings, but the damage was already done. Clemson will face Oklahoma in the winners' bracket game Tuesday, while Arizona State will play Tuesday's elimination game against South Carolina.