Traci Yoshikawa made sure Hawai'i's debut on college softball's biggest stage was a memorable one.

Yoshikawa blasted a two-run homer to right-center field in the top of the seventh to give Hawai'i a 3-2 victory over Missouri in the Women's College World Series opener today at ASA Hall of Fame Stadium in Oklahoma City.

UH (50-14) will play UCLA tomorrow. The Bruins routed Florida, 16-3, in a game ended after the sixth inning because of the eight-run differential rule.

For the second consecutive game, Hawai'i trailed going into the seventh inning. In the top of the seventh, Katie Grimes led off with a single to right-center and was replaced by pinch runner Dara Pagaduan. Yoshikawa then ripped the first pitch from Missouri's Kristin Nottelmann for her 12th home run of the season, and the Rainbow Wahine's NCAA-record 156th of the season.

"I had good contact. It was a good feeling off my hands. I was just hoping it was going over," said Yoshikawa, one of eight players in Hawai'i's lineup with at least 10 homers this season. "It went over, and it was the greatest feeling ever."

UH's Stephanie Ricketts (30-8) got the Tigers in order in the bottom of the seventh for the complete-game victory.

"There was no doubt that we were going to come back because we come back all the time," Ricketts said. "As you can see, one through nine, there's always a chance of the ball flying out."

Hawai'i's Alex Aguirre hit a 2-2 pitch from Nottelmann to right-center field for a home run with one out in the second inning to give the Rainbow Wahine a 1-0 lead.

Missouri tied it at 1 in the bottom of the third on an RBI double by Nicole Hudson, scoring Rhea Taylor, who led off with an infield hit and went to second on a throwing error by first baseman Amanda Tauali'i.

Taylor hit a lead-off home run to left field in the bottom of the fifth inning to give Missouri a 2-1 lead.

Hawai'i went down in order in the top of the first inning. Ricketts gave up a single and two walks with one out, but struck out the next two batters to get out of a bases-loaded jam in the bottom of the first.

Ricketts struck out six and walked three against the Tigers.

"Three runs is not a big deal. I felt like we should have scored four or five-plus, but our offense didn't come through," Missouri coach Ehren Earleywine said.

"I know Hawaii's offense will be the story of the day. They hit a couple of home runs. But at the end of the day, I think anybody in this tournament would be satisfied with giving them three runs."

Hawai'i stunned the tournament's top seed, Alabama, to qualify for the WCWS for the first time. Missouri is 51-12.

The Associated Press contributed to this report.

UCLA 16, ARIZONA 3, 6 INNINGS

Andrea Harrison homered twice and drove in six runs, Megan Langenfeld went 4-for-4 with a homer and four RBIs, and UCLA broke the Women's College World Series record for runs in a game.

Harrison hit three-run homers in the first and sixth innings as the Bruins (46-11) surpassed Alabama's World Series record of 14 runs scored in a shutout against Arizona last year.

The teams' combined run totals were also a World Series record. The game was shortened to six innings because of the mercy rule.

Langenfeld (12-1) provided the final blow with a two-run homer to left field to cap UCLA's nine-run sixth inning. She also threw five scoreless innings of relief after Tiffany DeFelice of Florida (48-9) tied the game with a three-run double in the second inning.

Stephanie Brombacher (34-7) gave up five earned runs in 2 1-3 innings, getting pulled after she threw a series of illegal pitches.

TENNESSEE 9, ARIZONA 0, 5 INNINGS

Ivy Renfroe struck out six in a spotless Women's College World Series debut, Erinn Webb and Jessica Spigner had two-run doubles and Tennessee took advantage of a wild outing by Arizona starter Kenzie Fowler.

Fowler (34-7) walked eight in two-plus innings marred by eight illegal pitches, including a pair of balks that brought in runs for the 15th-seeded Lady Vols (48-13).

It was the second straight mercy rule defeat at the World Series for eight-time national champion Arizona (48-12), which was eliminated in a 14-0 loss to Alabama last year.