Senior guard Will DeBerg scored 17 of his 20 points in the second half and sparked a huge momentum swing as No. 1-ranked St. Thomas moved into the national semifinals with Friday's 82-79 victory over No. 8-ranked Williams (Mass.) in the NCAA Division III men's basketball playoffs in Salem, Va.

The Tommies (30-1) erased a 12-point late first-half deficit and posted their biggest comeback victory of the season.

They will play at 5 p.m. Saturday Minnesota time against Mary Hardin-Baylor, a 69-66 comeback winner over St. Mary's of Maryland. That victor takes a trip to the April 7 NCAA title game.

The Toms have won 17 of their 18 postseason games over the last three seasons, including 11 of 12 in the NCAA playoffs. They ran their season win streak to 14.

St. Thomas tied a school record for season wins and another with 15 3-point baskets (15-of-25), including treys from six different shooters. In the second half, DeBerg made three treys and sank another long jumper with his foot on the bonus line.

Zach Riedeman added 15 points and John Nance had 10 points and six assists. Tommy Hannon, playing in his 100th career game, contributed nine points and nine rebounds. Marcus Alipate had nine points, and Erik Tengwall had eight points and seven boards.

James Klemm had 20 points and seven rebounds and Taylor Epley added 16 points to lead Williams. Nate Robertson added eight points and 11 assists.

UST's 45-24 advantage in 3-point scoring offset torrid field-goal shooting by the Ephs (26-5), who made 65 percent in the first half and 58 percent on the game.

St. Thomas' pressure forced Williams into 11 second-half turnovers. That helped UST overcome 47-35 halftime deficit. The Tommies used a 20-9 advantage in bench scoring and a 15-2 mid-game run to recover from a poor start which produced Williams leads of 18-7 and 47-35.

The Toms trailed 63-62 when Riedeman made two free throws with 8:36 to go to start a 9-0 run and erase the final Williams lead.

The Tommies had a late eight-point lead but made it interesting with two missed free throws and a turnover on back-to-back possessions in the final 40 seconds. Williams had the ball with a chance to tie with :09 remaining but was unable to make either of two late attempts with the clock expiring.