COLUMBUS—For a half, David Lighty was almost invisible.Then it was as if he was invincible, refusing to let No. 2 Ohio State falter again.Lighty scored 17 of his 21 points in the second half and William Buford had all 17 of his in the first to lead the Buckeyes to a big bounce-back win after two recent losses, beating Illinois 89-70 on Tuesday night.During one remarkable 3-minute span, Lighty scored all 13 of Ohio State’s points (to just two for the Illini) and had three steals.The Illini scored 11 of the first 13 points of the second half to pull within 49-43 before Lighty took over.He scored Ohio State’s next 13 points to build the lead back to 62-45.Just that quick, the Illini responded with an 8-0 run to narrow the gap to 62-53.Lighty then fed substitute forward Deshaun Thomas, caught in a recent shooting slump, for a 3-pointer. Seconds later, Lighty missed a jumper and Thomas fought off a defender for the rebound and converted it into a three-point play for a 68-53 lead.Between them, Lighty and Thomas accounted for all 19 Ohio State points over a span of 7 1/2 minutes.The lead never dipped below double figures again.Jon Diebler had 13 points, Aaron Craft 12 and Jared Sullinger 12 points and 11 rebounds for the Buckeyes (26-2, 13-2 Big Ten), who had lost two of three after winning their first 25 games. hio State shot 53 percent from the field to end Illinois’ string of 37 consecutive games holding an opponent under 50 percent. The last team to reach 50 percent was also Ohio State, which shot 53.1 against the Illini on Feb. 14, 2010.The Buckeyes had just three turnovers – they forced 16 turnovers, including getting nine steals.Mke Davis scored 18 points, Mike Tisdale 14 and Jereme Richmond 11 for Illinois (17-11, 7-8), in dire need of more wins to make the NCAA tournament field. Demetri McCamey, the 12th-leading scorer in the Big Ten at 14.5 points a game, did not start for the Illini but finished with 15 points and six assists.The Buckeyes had lost at Wisconsin on Feb. 12, beat Michigan State at home last week and then dropped the game to the Boilermakers. With four games left and a one-game lead in the Big Ten, they knew they couldn’t afford another slip.