CHAMPAIGN, Ill. - With Ohio State down by eight and just under 13 minutes to play, Jared Sullinger assured his teammates that this one was in the bag.

"Don't worry, don't worry," the freshman sensation said over and over as he and the Buckeyes gathered for a timeout.

No. 1 ranking and undefeated season on the line. Big Ten road game at No. 23 Illinois.

Nothing to worry about, right?

Yeah, as it turns out, right.

Sullinger had 27 points and 16 rebounds while playing all 40 minutes, and the Buckeyes scored 14 straight points in the second half to rally past Illinois 73-68 on Saturday.

"I felt like Jared was pretty good today," Ohio State coach Thad Matta deadpanned, then waited a beat for the reporters in the room to take in what he'd said. "That was a joke — he was awesome."

Sullinger was 13 for 15 at the free throw line and scored Ohio State's first nine points of the second half, keeping his team in the game when none of his teammates could find the basket.

And finally, when Illinois' last gasp ended, it was Sullinger, sitting in the lane grinning and holding the ball, signaling that it was over and the Buckeyes (20-0, 7-0) could relax.

"Pride, heart and composure," Sullinger said. "Those three things — we really showed a lot of composure."

None of it, though, came easy.

Trailing 34-33 at halftime, the Buckeyes came out cold. Sullinger's nine points over the first 6:30 were all they could muster.

Matta said afterward that Sullinger would have been just as happy if someone else was scoring the points, as long as the result was the same.

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"He's a special young man," Matta said. "His humility — he's all about winning."

Jereme Richmond had 18 points and 10 rebounds for Illinois (14-6, 4-3), and Mike Tisdale added 15 points. Demetri McCamey, who leads the Illini with 16.2 points a game, scored just five on 2-of-11 shooting.

Still, when Mike Davis' layup dropped with 12:51 to play, Illinois was up 50-42 and Matta called a timeout.

That's when Sullinger, waving his arms like a football referee signaling an incomplete pass, told his teammates they shouldn't worry.

They must have listened.

Starting with a pair of free throws by Jon Diebler with 11:39 left and ending with a 3-pointer by Deshaun Thomas with 7:47 to go, the Buckeyes went on a 14-0 run that gave them a 56-50 lead.

"We started playing a little tentative, they turned up the pressure," Tisdale said. "They made plays, we didn't."

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The Illini, though, still had a run left in them.

Down 68-61 with 2:12 to play, they scored seven of the next eight points, the last of them on a 3-pointer by the 7-foot-1 Tisdale to close to 69-68.

The Illini were forced to foul Aaron Craft, who sank both free throws for a 71-68 Ohio State lead with 15 seconds left.

The Illini brought the ball back up and McCamey flipped it to Tisdale as he moved inside toward the basket. Diebler stripped the ball from Tisdale's hand and Sullinger, heading to the floor, latched onto it to seal the win.

Talk in Illinois for much of the week centered on the last time the two teams met with one undefeated, in March 2005. Ohio State ended Illinois' unbeaten run that season, though Illinois went on to play in the NCAA title game, losing to North Carolina.

Sullinger's brother, J.J., was part of that Buckeyes team.

The younger Sullinger lived up to his billing, often dealing with two Illinois defenders, but not quite often enough, he said.

"They came with like a semi-double — if I went to the middle, the other big would just sit there in the middle," he said. "It really wasn't a (true) double team, so I was able to do what I could do."