IOWA CITY, Iowa -- Iowa coach Fran McCaffery kept telling struggling sophomore Josh Oglesby to take open shots, even though the numbers suggested he shouldn't.
Oglesby rewarded his coach's faith with crucial back-to-back 3s that buried Illinois.
Devyn Marble scored 21 points and Iowa beat the Illini 63-55 on Tuesday night for its fifth win in seven games.
Oglesby added 10 for the surging Hawkeyes (19-11, 8-9 Big Ten). They tied a school record with 12 blocked shots, including six from Gabe Olaseni off the bench.
Oglesby -- a shooting guard shooting just 26.8 percent entering play -- buried two straight 3-pointers to turn a two-point lead into a 54-46 cushion with 3:19 left.
D.J. Richardson then missed a dunk and Marble followed with a three-point play that put Iowa ahead by 11 with 1:39 to go.
"He's tried so hard to do what he did (Tuesday) all the time. It would be different if he didn't put the time in, if he wasn't a great teammate," McCaffery said of Oglesby.
Brandon Paul had 18 points and nine boards to lead Illinois (21-10, 8-9), which lost for just the second time in eight games.
The Illini made just nine shots in each half and let Iowa go on a game-deciding 9-0 run in the closing minutes.
"I thought our guys were tentative in the second half. I didn't think we were sharp in the second half," Illinois coach John Groce said. "Iowa did a really good job of defending us in the second half. But we have to make a few more plays. Oftentimes, that's what it is."
Perhaps Iowa's biggest issue has been its inconsistent shooting. But it's hard to remember the Hawkeyes shooting anywhere near as poorly as the Illini did for long stretches Tuesday.
Illinois missed 15 of its first 16 shots -- a stretch of futility that included layups, mid-range jumpers and ill-fated 3s -- as Iowa jumped ahead 15-4.
Still, the Illini fought their way back into it. They grabbed 10 offensive rebounds, turned it over just four times and pulled within 31-28 at halftime. But the issues that plagued Illinois to open the first half came back for the start of the second.
The Illini missed their first five attempts as Iowa moved back ahead 36-28. They scored just three points in 8 minutes as the Hawkeyes stretched their lead to 41-31.
"I'm disappointed in the way we came out both halves, especially with older guys out there. Very disappointed. We've got to get corrected," Groce said. "It shouldn't happen. I've got 21, 22-year-old-plus guys that have been doing this for a while, and we've got to be ready to play."
The Illini pulled within 48-46 before Oglesby made arguably the two biggest shots of his young career.
"Just keep believing. Just keep shooting. Coach (McCaffery) had told me that all year," Oglesby said. "Early on, my shot wasn't falling. It was obviously frustrating, but then I made those two and it felt good."
Richardson had 13 for Illinois, which also hit just 10 of 17 free throws.
Though Illinois has beaten Gonzaga and Indiana, the top two teams in this week's AP Top 25, it will be seeded in the Big Ten tournament behind Iowa -- still a long shot, at best, for the NCAA tournament -- if the Hawkeyes beat Nebraska at home on Saturday.
Marble now has 998 career points. When he reaches 1,000, he'll join his dad, Roy Marble, as the only Big Ten father-son duo to each reach that total.
But Marble's milestone will likely have to wait until the weekend against Nebraska. The stars for a Hawkeyes team in need of every win it can get were Oglesby and the ever-improving Olaseni -- who had more blocks Tuesday night than he had in all his other Big Ten games combined this season.
"Fortunately we had Gabe back there. And he was taking care of business," McCaffery said.