OKLAHOMA CITY — It was Traci Yoshikawa's turn to add a chapter in the growing tale of the 2010 University of Hawai'i softball season.

The senior second baseman hit a two-run home run in the top of the seventh inning to lift the Rainbow Wahine over Missouri, 3-2, yesterday in the first game of the Women's College World Series at ASA Hall of Fame Stadium.

"These games are a part of what we're all about this year," said Hawai'i coach Bob Coolen, whose team has won its last three games in its final at-bat. "This year is special."

The 16th-seeded Rainbow Wahine (50-14) play fifth-seeded UCLA (46-11) at 1 p.m. Hawai'i time today. UCLA demolished fourth-seeded Florida (48-9), 16-3.

Yoshikawa had a good idea what Missouri pitcher Kristin Nottelmann (24-8) might throw when she entered the batter's box after Katie Grimes singled to start the seventh with Hawai'i trailing, 2-1.

"I was looking for an outside pitch for sure; that's her go-to pitch," Yoshikawa said. "She had been going to the outside pitch all day. ... I just threw my hands out to the ball and as soon as I hit it I knew it was over the wall."

Said Nottelmann: "I think I might have wanted to switch and go to the inside instead of away, but I felt we could have gotten her out away ... it's just tough whenever those kinds of things happen."

It was Hawai'i's second home run of the afternoon.

Alex Aguirre delivered a 230-foot solo shot to give the Rainbow Wahine a 1-0 lead in the top of the second inning.

"Just seeing it get over the fence,it was a big relief," said Aguirre,who lined the 2-2 offering over the wall in right-center field. "It said, 'We're here, and we're making a statement.' "

Hawai'i pitcher Stephanie Ricketts (30-8) had already made a statement of her own against the ninth-seeded Tigers (51-13), escaping a bases-loaded jam in the first inning.

Missouri's Jenna Marston started the trouble with a one-out single, and then Ricketts aided the Tigers' cause by issuing walks to Nicole Hudson and Ashley Fleming. The inning was extended when shortstop Jessica Iwata dropped a pop foul.

"I really don't think about the pressure," Ricketts said. "I was just thinking, 'Calm down, there are six other innings, so if something happens you'll be fine, but don't let anything else happen.' "

And she didn't, striking out the next two batters to retire the side.

"That first inning we had bases loaded and one out and two strikeouts back to back, and you just can't do that, we should have put the ball in play," said Missouri coach Ehren Earleywine, whose team plays Florida in an elimination game tomorrow.

"If someone would have told me before the game Hawai'i would only score three runs, I woulda said 'Sweet, we can win that game.' "

The Tigers tied the score at 1 in the bottom of the third when Hudson drove a double over leaping right fielder Kanani Pu'u-Warren, enabling leadoff hitter Rhea Taylor to score from second. Taylor had reached on an infield single and advanced to second when first baseman Amanda Tauali'i threw errantly to Yoshikawa, who was covering first on the slap hit.

The Tigers took a 2-1 lead when Taylor led off the fifth inning with a solo homer that just cleared the left-field wall.

Coolen made an adjustment to Ricketts' pitching, encouraging her to adjust the speed of her change-up and throw it more often.

"We went to it late because she felt good about it," Coolen said. "We hadn't thrown it a lot early; we knew we had them off balance."

Ricketts finished with a six-hitter, allowing one earned run while walking three and striking out six.

The offense, Coolen knew, would take care of itself.

"The second Traci hit (the home run), I knew it was out," Coolen said. "We had placed her in slap mode, so she could time the pitcher and use her legs, and she stayed in the rhythm of the pitcher.

"It was an exciting first game for us. It's a tribute to the players; they never give up."

NOTE: UCLA's 16-3 win over Florida represented the most runs scored in the 29-year history of the WCWS, and marked the Bruins' third consecutive run-rule victory in the NCAA Tournament. It was the most runs scored against Florida since 1999, when Tennessee handed the Gators the worst loss in the history of their program, 18-1.