COLUMBUS, Ohio -- Jon Diebler had the biggest of the game's 17 3-pointers.
Ohio State (No. 16 ESPN/USA Today, No. 17 AP) led by 18 points early in the second half against Jacksonville on Wednesday night, only to see the Dolphins close within five with 5 minutes left.
Diebler hit his third 3 of the game and the Buckeyes were able to hold on for an 81-68 victory that kept them undefeated on the season.
"We knew what exactly what play they were going to run for Diebler, either coming off the baseline screen or coming off the down screen coming through the top," Jacksonville coach Cliff Warren said. "We were late in guarding that particular play."
The Buckeyes shot 64 percent from the field (27-of-42) but only 63 percent (17-of-27) from the free throw line.
"I swear to you we're working on it," Ohio State coach Thad Matta said of the poor free throw shooting.
It was a different story from beyond the arc.
The Buckeyes made nine of their first 13 3-point attempts and finished 10-of-17 (59 percent).
"I thought it was uncharacteristic of our defense to let them shoot that well," Warren said. "I don't think anyone has shot that well against us in years. They made the open shots."
Diebler, Lighty and Simmons hits 3s in the opening 3 minutes of the second half to build a 56-37 lead. The Dolphins got within 67-61 with 6:46 remaining after Jefferson made consecutive 3-pointers.
Jacksonville shot 49 percent (26-of-53) from the field, including 7-of-17 on 3s.
"We let them shoot 50 percent tonight and that's the first time this season we've allowed that," Lighty said. "We need to go back to the drawing board and fix ourselves defensively so that doesn't happen again."
After a jumper by Lighty, Jacksonville's Brian Gilbert made it 69-64 with a 3-pointer before Diebler responded with his 3 to put the game away.
"Jon has been tremendous in his work ethic," Matta said. "I have no problem having Jon taking a big shot. [The play] came up in the shootaround this morning. Jon made a good read."
Ohio State was up 45-34 at halftime, but the lead was anything but comfortable. The Dolphins erased all but one of an early 12-point deficit and hung close until two 3-pointers from William Buford and another by Simmons in the final 3 minutes.
Jacksonville got within 59-51 with 12:06 to play on a layup by Colbert only to see Turner make a reverse layup to restore the 10-point lead.
Lighty scored seven points in the opening 6 1/2 minutes as the Buckeyes took an 18-6 lead. Jacksonville closed the gap to 22-21 on a free throw by Aric Brooks with 7:54 remaining.
The Buckeyes could not handle the press and Tevin Galvin stole the ball, but Brooks missed the layup that would have put Jacksonville ahead and Lighty went the length of the court for a layup.
"They did a great job capitalizing on our mistakes," Warren said.
Jacksonville twice got within two points before the Buckeyes led 32-27 with 3:44 left in the half on two free throws by Lighty.
"They scored a lot and we weren't ready for it," Turner said. "We saw them shoot and have openings but we were not reacting quickly enough. The type of defense we played tonight is not the type of defense that we emphasize at the Ohio State University."
The Buckeyes led 45-34 at halftime.
"We beat a very good team," Matta said. "Their record is definitely not indicative of the team they are. For whatever reason, we just were not in the game defensively. We just lacked tenacity and toughness and we were very fortunate to come out on top."