DiLeo's 24 points matched his season high. Larry Austin Jr. added 20 points and dished out nine assists for the Chippewas, who improved to 21-10 and finished 10-8 and in fifth place overall in the MAC.
Shawn Roundtree Jr. added 14 points for the Chippewas, who made 50 percent (32 of 64) of their field goal attempts.
CMU is the fifth seed in the MAC Tournament and will open on Monday, March 11 (7 p.m.) at McGuirk Arena against the Broncos (8-23, 2-16). The winner heads to Cleveland for the tournament quarterfinals on Thursday, March 14.
The win was CMU's first at Western since the 2008-09 season as CMU swept the season series from its in-state MAC rivals, the Broncos and Eastern Michigan.
"This team continues to not let one play upset them the next (play)," CMU coach Keno Davis said. "We came up with some big stops and knocked down free throws."
HOW IT HAPPENED
The Chippewas opened a 41-26 halftime lead, and extended their advantage to 21 points, 65-44, with under 11 minutes remaining. The Broncos stormed back with a 22-5 run, cutting their deficit to four, 72-68, with just over two minutes to play.
Back-to-back jump shots from DiLeo and Shawn Roundtree Jr. quelled the rally and then DiLeo and Austin combined to make all four of their free throw attempts in the waning seconds to hold the Broncos at bay.
Seth Dugan scored 26 points and grabbed 15 rebounds to lead Western.
AUSTIN MAKES HISTORY
With five steals, Austin upped his season theft total to a program-record 68. Dave Grauzer set the previous mark, 63, in 1978-79.
Austin's nine assists gives him 179 for the season, good for third most in a season in program history. Grauzer set the mark, 196, in '77-78 and Chris Fowler is second with 194 in '14-15.
SCARY MOMENT
Friday's game was delayed for 60 minutes when referee Ed Phillips collapsed on the court. Phillips reported shortness of breath and chest pains. He was transported to a nearby hospital where he was reportedly in stable condition late Friday night. The remainder of the game was played with two officials, Bart Wejenke and Paul Szelc.
"Our guys understood that (Friday's) game may not have been played," Davis said. "We might have had to come back (Saturday), two hours later, or not at all. The basketball was definitely secondary.
"Our prayers and thoughts are with that official, so it kind of puts things into perspective with a situation like that."