PORTLAND, Ore. — Western Kentucky is at it again.

The 12th-seeded Hilltoppers, who made an unexpected run in the NCAA tournament last year, pulled off a first-round upset of fifth-seeded Illinois, 76-72 tonight in the South Regional.

Steffphon Pettigrew had 17 points to lead Western Kentucky (25-8) which led by as many as 17 points but had to hold off a late charge by the Illini (24-10). It was the 19th time in the last 21 years that a 12 seed has beaten a No. 5.

Trent Meacham had a season-high 24 points for the Illini, who were without senior defensive specialist Chester Frazier, who had surgery on his right hand last week.

Western Kentucky will face Gonzaga (27-5) in the second round.

Western Kentucky looked as if it would cruise to this upset, but Illinois made a late run and turned it into a one-possession game in the final minute.

Calvin Brock's layup for the Illini made it 71-66 with 1:11 to go. Orlando Mendez-Valdez missed a long-jumper for Western Kentucky, and Anthony Salley was called for goaltending on Jeff Jordan's fast-break layup to make it 71-68.

Pettigrew made a pair of free throws before Meacham scored on a baseline drive to narrow it to 73-70.

A.J. Slaughter hit one of two foul shots to give Western Kentucky a slight cushion, but Meacham's layup made it 74-72. Illinois tried to foul immediately, but didn't get the call in time and Anthony Salley hit free throws with 0.9 seconds on the clock.

When the buzzer sounded, Slaughter calmly pumped his fist like he'd been there before.

Western Kentucky grabbed attention last season with a tear to the regional semifinals. As the 12th seed, the Hilltoppers defeated Drake 101-99 in overtime, then beat San Diego 72-63 before falling to UCLA.

With the key players on that team gone and a new head coach, Western Kentucky was considered a longshot to even return to the tournament. But the Hilltoppers rolled through the Sun Belt to earn an automatic bid.

They came to Portland with a seven-game winning streak.

A 15-2 run in the first half, capped by Matt Maresca's put back, made it 27-13 and Western Kentucky went on to lead by 37-28 at the break.

Pettigrew's 3-pointer put the Hilltoppers up 49-34 early in the second half.

Illinois closed to within 50-41 on Dominique Keller's jumper, but Sergio Kerusch and Jeremy Evans answered for Western Kentucky with a pair of statement-making dunks.

Mendez-Valdez made a 21-foot fadeway to stretch the lead to 61-46 midway through the second half. The Hilltoppers led by as many as 17 points.

After Kerusch scored to make it 70-55 late, Illinois guard Brock rolled his eyes, and looked to the scoreboard before heading sheepishly back down the floor.

The Illini were clearly affected by the loss of Frazier. The unquestioned leader of the team and one of the best defenders in the Big Ten injured his hand in practice last week and had surgery on Thursday.

After he missed the conference tournament — Illinois beat Michigan but fell to eventual champion Purdue — there was some speculation that Frazier might play in Portland, but coach Bruce Weber ruled him out on Wednesday.

Illinois was making its ninth NCAA tournament appearance in the past 10 years.