Paris Lee scored 18 points and made four assists, MiKyle McIntosh added 14 points and Illinois State never trailed in its 78-50 win over Indiana State on Wednesday night.
The Redbirds (17-11, 11-4) have won a season-high five straight games and have their best Missouri Valley Conference start through 15 games since 1997-98.
DeVaughn Akoon-Purcell scored 12 and Deontae Hawkins added 10. The Redbirds outscored the Sycamores 32-14 in the paint and outrebounded them 46-35.
Illinois State opened with a 21-4 run and never looked back, pulling to a 44-23 halftime lead on 58.1 percent shooting behind nine points each from McIntosh and Tony Wills.
Illinois State scored 10 unanswered points and pulled further away, 70-42, in the second half while the Sycamores missed six shots over four minutes.
Khristian Smith and Everett Clemons scored 14 apiece for Indiana State (13-14, 7-8), which has lost four straight.
>>Southern Illinois Survives Bradley
Sean O'Brien had 24 points including a pair of key baskets in the final 5:10 to help Southern Illinois hold off Bradley 71-59 on Wednesday night.
Anthony Beane, after missing his first 12 attempts from the field, had back-to-back 3-pointers down the stretch that were crucial in helping the Salukis (21-7, 10-5 Missouri Valley Conference) pull away.
Bradley (4-24, 2-13) had a 12-2 run to pull within 55-52 with 5:27 left. O'Brien hit a jumper to stop the run and Beane followed with the two 3s - his only points of the night. O'Brien added a 3 to make it 66-55 with 2 minutes left.
Mike Rodriguez scored 14 points and Bola Olaniyan had 11 points and 11 rebounds for Southern Illinois.
Donte Thomas had 17 points and Dwayne Lautier-Ogunleye scored 12 for the Braves. Thomas scored six during the late run that pulled Bradley within three.
>>Duke Stuns North Carolina For Big ACC Win
Grayson Allen scored 23 points and Derryck Thornton came up with the clinching block on the final play to help Duke edge No. 5 North Carolina 74-73 on Wednesday night.
Allen hit a pair of free throws with 1:09 left for the lead. Then Duke (20-6, 9-4 Atlantic Coast Conference) came up with a pair of stops in the final minute, finishing strong after trailing most of the way while North Carolina's Brice Johnson put together a huge performance.
As coach Mike Krzyzewski put it, his Blue Devils ''just hung in there.'' And by the end, a team that basically relied on five players the entire second half after losing Matt Jones to a first-half injury was the one making veteran plays on the road.
Duke got its first critical stop on a shot attempt inside in traffic by Kennedy Meeks. Then, in the final sequence, Johnson rebounded Allen's miss and UNC pushed the ball up the court for a final shot without calling timeout in the final 20 seconds.
That's when Thornton blocked Joel Berry II's hurried shot in the lane. Allen rebounded the ball and flung it into the air to let the final seconds expire, then raced with the rest of the players straight to the Duke bench to celebrate.
Johnson had 29 points and 19 rebounds for North Carolina, which came in with a decided edge in size and depth. But Johnson got little help outside of Justin Jackson's 13 points, with the Tar Heels sputtering down the stretch after leading by eight with about 7 minutes left.
Johnson got just two shot attempts in the last 13 minutes.
Duke freshmen Brandon Ingram (20 points) and Luke Kennard (15 points) had huge baskets down the stretch. Ingram, a prized recruit who passed on UNC, scored three straight baskets after the Tar Heels took their biggest lead at 68-60 with 6:49 left.
Kennard came up with a 3-pointer at the 2:39 mark for a 72-71 lead, Duke's first lead since midway through the first half.