Senior center Keke Carrier scored 20 points and pulled in a career-high 19 rebounds to lead the Tigers. Her rebound basket with 1:05 left to play put the Tigers ahead for good on a night in which they struggled with their shooting.
Coach Nell Fortner's team had to rally from a six-point deficit with less than four minutes to go after leading most of what she called an "ugly" game by her Tigers.
Auburn hit just 19-57 field goals and was 0-9 on three-point attempts, but managed to improve its record to 9-3. However, the victory wasn't secured until 0.2 was left on the clock when freshman guard Laura Richards made her first foul shot and missed a second one that kept the game from going to overtime.
A 10-foot jump shot by Auburn freshman point guard Morgan Toles, with 30 seconds left, proved to be the winning margin. That put the Tigers up 51-47.
The Crusaders, who fell to 3-7, cut the lead to two points with 12 seconds left and then fouled Alli Smalley. The junior missed the front end of a one-and-one to set the stage for a too close for comfort ending for the Tigers.
"I don't what to say," Fortner said after the game. "We rebounded well. I think that is probably the reason why we won the game."
With Carrier leading the way on the boards, the Tigers enjoyed a 51-32 edge in rebounds. The senior also blocked a half dozen shots. "I thought Keke was a real warrior tonight," Fortner said.
Valparaiso hit just 18-57 field goals, but kept the game close by making seven three-pointers.
Jordan Greenleaf scored 15 points for the Tigers and added nine rebounds. Auburn returns to action in the championship game of the event on Wednesday at 9 p.m. CST vs. host San Diego State, which advanced to the finals with a 63-62 win over Wake Forest.