Turner had 21 points and ignited a second-half rally with nine points and two blocked shots to guide the Buckeyes to a 71-53 victory over Iona on Saturday.
The Buckeyes (8-0) relied on a 13-5 run midway through the second half to quickly erase a deficit -- right after coach Thad Matta ripped into his team during a timeout.
"Your security blanket is not here," Matta said he told his players, referring to Lighty. "It's time to play basketball."
Asked how he was doing, Lighty flashed a grin and said, "I'm good -- we won."
Ohio State extended the nation's longest winning streak to 13, including the final five games a year ago when it won the NIT.
Iona took a 31-28 lead with a rapid 7-0 run to start the second half, capped by Scott Machado's 3-pointer.
A disgusted Matta signaled for a timeout.
"He yelled at us at the beginning of the second half," Turner said. "He was reminding us that everybody had to play hard because we didn't have David. Everyone accepted the challenge."
Turner tied it with an immediate 3 and then began to take over the game. With Ohio State clinging to a 38-35 lead, he hit a 15-foot jumper and then blocked shots on the next two Iona possessions. In between, Jeremie Simmons followed his own missed layup off the break and, after the second block, Simmons flipped an alley-oop pass to Buford for a dunk.
"I saw Will in the open court and I just put it up for him," Simmons said.
Buford, Ohio's Mr. Basketball last year as a high school senior in Toledo, had played only 25 minutes the last two games. But he was on the court for 32 minutes with Lighty out of the lineup.
"I tried to prepare myself," Buford said. "I tried to work harder on defense because I knew if I worked hard on defense the offense would come."
Turner said it was important to turn things around on the Gaels before they gained confidence.
"You always want to stop momentum," he said. "Momentum can be your best friend or your worst enemy. It was our best friend right there."
Turner then hit a hanging 12-footer and two free throws to push the lead to 48-37.
"Evan Turner is a special player," Iona coach Kevin Willard said. "He's fun to watch."
The Gaels never got closer than seven points again.
Turner said that Lighty, the Buckeyes' third-leading scorer at 9.7 points a game, kept encouraging his teammates.
"He has a lot of faith in us," Turner said. "He's the most optimistic person I've ever met. He always believes in us. We could go up against an NBA team, and he'd believe we would beat them."
Matta said he and his staff didn't really know what to expect of the Buckeyes. On a team with no seniors, Lighty is the most experienced player with 83 games and 51 starts.
"You felt like you had something going, you were building something, and then you lose a player -- an important player," Matta said. "We said we've got to get their mind-set to be, hey, just find a way. In the second half, we got it going."
Willard, who has two players of his own wearing casts, said even without Lighty the Buckeyes were a handful.
"They lose a lot, but they have really good weapons out there," he said.
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