But Saint Louis U. battled back with a 25-5 run to take the lead made the key plays the Billikens needed down the stretch to secure a 69-64 win.
"I thought the guys played their hearts out," SLU coach Rick Majerus said. "There were a lot of mistakes from inexperience and nervousness. We're essentially playing a varsity schedule with a frosh-soph team. I thought the guys played their hearts out tonight, especially in the middle of exam week."
Freshman guard Jordair Jett scored a game-high and career-high 16 points. Freshman forward Dwayne Evans recorded the first double-double of his career with 12 points and 11 rebounds. Freshman guard Mike McCall had nine points and a career-high eight assists.
The comeback was the largest for the Billikens (4-4) since rallying from 18 points down against North Carolina A&T on Jan. 2, 2009.
"We just clawed back," said Cassity, who finished with 14 points and went six of six from the free throw line. "When you're down 18, that's all you can do. If you give up, they are just going to pour more on you. You can't ever give up and that's basically what we did."
The SLU starting lineup on Wednesday featured four freshmen — Jett, McCall, Evans and forward Rob Loe — and one junior, Cassity. And the results weren't easy on the eyes in the first half as the Billikens trailed by as many as 14 points before going into halftime down 31-21.
"We played better in the second half, 110 percent," Cassity said. "I mean there's no comparison. I thought we guarded decently in the first half. We missed a lot of good shots. But the second half was when we really kicked it up. I don't know what we were down at one time but that has to be close to one of the biggest comebacks we've had since I've been here."
Jacksonville (6-3) opened the second half with a 12-4 run to push its lead to 18 and during that stretch Cassity was knocked to the floor.
"I don't know what I ran into but it was something tough and hard and it hit me pretty good," he said.
The comeback began with the most unlikely of shots, the first 3-point attempt of Evans' career. The freshman forward knocked it down from the top of the key.
"He's not allowed to shoot 3's," sophomore forward Cody Ellis said. "In practice, Coach has put in a rule that he's not allowed to shoot 3's yet."
"He knocked it down, though," Cassity said. "It looked pretty good."
Evans followed the 3-pointer with a breakaway dunk assisted by McCall and then SLU got a putback by Loe. After a 3-pointer from Jacksonville, the Billikens knocked down three more 3-pointers, from Loe, Ellis and Jett as part of a 12-0 run.
After a mid-range jumper by Jacksonville, SLU got a bucket inside from sophomore forward Cory Remekun and two lay-ups from Jett to take a 50-48 lead.
In a span of eight minutes, SLU had outscored Jacksonville 25-5.
"Our defense, that's what started working," Ellis said. "We guarded real well. All the freshmen stepped up. They were real clutch. It all started on the defensive end and that floated to our offense."
The Billikens, who outscored the Dolphins 44-21 in the final 16 minutes, never trailed again.
Saint Louis U. made six of seven free throws in the final minute to seal it.
"That was a nice win," Majerus said. "I'm really proud of them and happy for them. (Jacksonville) should win their league. This team beat Auburn at Auburn and they're a good team. We played them with the idea that it would help our RPI. That's the least of our concerns now."