Dan Leslie's walk-off single through the left side of the infield scored Matt Olson in the bottom of the 12th inning as the University of St. Thomas (Minn.) defeated The College of Wooster (Ohio) by a final tally of 3-2 in the title game of the NCAA Division III Baseball Championship on a soggy day at Fox Cities Stadium.

"Once we got out of the 12th, I knew I was going to come up [to bat]," Leslie said. He had grounded into a pair of double plays his last two times at the plate. "I was looking for a pitch and hit it hard."

The victory caps an improbable run to the national championship for St. Thomas. It's the second national title and first since 2001 for the Tommies (41-13), who were playing in their third elimination game of the tournament.

"As long as we kept playing good defense and got good pitching, I was confident we could stay with them," St. Thomas head coach Dennis Denning said. "We definitely were the underdog."

St. Thomas was able to force a second title game by rallying for a 6-4 decision over the Fighting Scots, which had not yet lost in the double-elimination tournament, and the nation's winningest pitcher in Justin McDowell (13-3).

Trailing 4-1 heading into the bottom of the sixth of game one, Wooster's Shane Swearingen lead off with a solo home run down the left field line -- his first homer of the season -- and Stu Beath drove in two more runs on a double to right-center field to tie the game at 4-4.

The Tommies plated the go-ahead run and tacked on another with back-to-back RBI singles by Brian Schmitz and Leslie in the top of the ninth. The hits forced a second and decisive game with Wooster, while starting pitcher Matt Schuld held on for the complete-game victory to improve to 12-1 on the mound.

In game two, St. Thomas grabbed an early 1-0 lead in the bottom of the third inning on a run-scoring single by Tim Kahle that never left the infield.

Wooster responded by taking its first lead of the afternoon in the top of the fourth on a two-run blast by Matt Groezinger, but the Tommies evened it back up at 2-2 on a sacrifice fly by Roy Larson in the sixth.

With two outs and runners on second and third, Wooster starting pitcher Mark Miller intentionally walked St. Thomas leadoff batter Matt McQuillan to load the bases. He then got pinch hitter John Means to ground out to second base on a diving stop by John Warren to extend the game before Leslie delivered the game-winner.

"It was two great games," Wooster head coach Tim Pettorini said. His Fighting Scots were making their fifth championship appearance and finished the season with an overall record of 43-11. "I give St. Thomas a lot of credit. I know how hard we battled, and they were just a little bit better. Congratulations to them. They deserved it."

Miller picked up the loss, while Brandon Stone was credited with the win. Stone came in for St. Thomas starter Bryce Gapinski in the sixth and allowed just three hits while striking out four in seven innings pitched.

"Our defense has been good all year, so I knew if I just did my job, they would make the plays, and they did," Stone said.

The Tommies accepted an at-large bid into the NCAA Division III Baseball Championship after falling to St. Olaf twice on the final day of the Minnesota Intercollegiate Athletic Conference tournament. St. Thomas went on to sweep St. Olaf in the Oshkosh regional last week and won three elimination games in a 24-hour period to advance to the World Series.

"We went from our conference tournament to the regional, and every game was close," Denning said. "Our kids played well when it counted."

The 12-inning marathon tied for the second-longest championship game in the history of the NCAA Division III Baseball Championship finals.