Trey Calvin answered with a 3-pointer for the Raiders, but Diggins scored two more baskets in a row to push the WSU deficit to 21 points with under 14 minutes to go.
Wright State never challenged after that, trailing by as many a 27 en route to a crushing defeat that almost certainly ends their hopes of making a fourth NCAA Tournament despite the best regular season for the program since joining Division I.
Bill Wampler scored 14 to lead the Raiders, who shot 29 percent from the floor and were outrebounded 46-33.
“Early we kind of let our offense affect our defense and when you’re going through offensive struggles it should be the other way around:,” said WSU point guard Cole Gentry, who had five points and four assists. “You’ve got to get yourself going on the defensive end and then you can kind of get out of that whole offensively, but we missed a lot of shots early in the game and they just kept going and kept going.
“When you fall behind by 10 and then 15, it feels like every shot needs to go in. You have to take it possession by possession and it’s hard to do that when you just can’t make shots.”
Tarkus Ferguson was the star of the game, scoring a game-high 25 points for the Flames, who shot 51.7 percent from the floor and outscored Wright State 38-20 in the paint.
“Part of what went wrong was UIC,” Wright State coach Scott Nagy said. “They’re good. Coming into this game they’d won 11 out of their last 15. They’ve gotten healthy and Steve (McClain) has them playing well. They’re the best defensive team in the league and I think that UIC is what went wrong.”
FIRST HALF RECAP:
UIC leads Wright State 41-26 at halftime of their Horizon League basketball tournament semifinal at Indiana Farmers Coliseum.
No. 1 seed Wright State got off to an awful start and did not finish the half particularly strong, either.
The fourth-seeded Flames made 5 of their first 6 shots and opened up a 13-6 lead in the first four minutes.
While UIC could hardly miss, the Raiders were 1-for-3 from the field, 3-for-6 from the free-throw line and guilty of a pair of turnovers.
The best thing that happened for Wright State in the first four minutes was drawing four fouls on the Flames.
The Raiders got within five briefly but quickly were down double-figures again.
Aside from a two-minute period where they hit three 3-pointers, the regular season champs struggled to do much of anything right in the first half.
They shot 26 percent from the floor and were outrebounded 24-14.
UIC shot 52 percent from the floor and had an 18-6 advantage in points in the paint and outscored WSU 11-2 in transition.
The Raiders were in the bonus for most of the first half but did little to capitalize, missing half of their 16 free throws.
Jaylon Hall led Wright State with five points in the first half while Raider stars Loudon Love and Bill Wampler both struggled.
Wampler was 1-for-6 from the field while Love made only one of his four tries and also missed three of his four shots from the charity stripe.
All-Horizon League guard Tarkus Ferguson starred for UIC with 16 points.