EVANSTON—No one could have blamed Thad Matta for letting out a sigh of relief. Top-ranked Ohio State’s coach expected a difficult time against Northwestern, and that’s exactly what the unbeaten Buckeyes got Saturday night.They also found a way to capture their 22nd straight victory, thanks to a late steal from veteran David Lighty and a tie-breaking free throw from freshman star Jared Sullinger to pull out a 58-57 victory over the short-handed and determined Wildcats.Once again it was Sullinger coming through for the Buckeyes. Northwestern had a chance to take the lead, but Lighty stole a pass near the basket with 17 seconds to go. And the Buckeyes then worked the ball into the 6-foot-9, 280-pound Sullinger.He was double-teamed throughout the game and in this instance, once he got the ball to go up near the basket, he was fouled. With Northwestern’s student section trying to distract him with waves and screams, he hit the rim with his first attempt and swished the second.After three timeouts, NU got a long attempt from Drew Crawford that hit the backboard.Sullinger finished with 21 points and Aaron Craft had 13 points for Ohio State. Leading by only two at the half, Ohio State (22-0, 9-0 Big Ten) pulled out to a 13-point lead in the second half with a 14-4 run. But Northwestern, playing without leading scorer John Shurna because of a concussion, came back behind senior guard Michael Thompson, who led the Wildcats with 16 points — 13 in the second half.Thompson’s 3-pointer with 3:51 left capped a 21-7 run as the Wildcats took a 55-54 lead and the crowd at Welsh-Ryan Arena erupted.Ohio State’s Jon Diebler — No. 5 all-time in the Big Ten in 3-pointers made — hit one for his first basket of the game to put the Buckeyes right back in front 57-55.Thompson then sailed through the lane and the 5-foot-10 guard floated the ball into the basket for a tie with 1:31 left.After an Ohio State turnover and then a foul, Northwestern retained possession and tried to set up a go-ahead shot. But Lighty foiled it.Northwestern (13-8, 3-7) fell to 0-16 all-time against top-ranked teams.Thompson’s 3-pointer with 7:53 left cut the lead to nine, and Ohio State’s Dallas Lauderdale was called for an intentional foul on the play near the basket. Davide Curletti made 1 of 2 free throws and the Wildcats retained possession with JerShon Cobb hitting a 3-pointer. The seven-point possession made it 51-46 with just a little more than seven minutes remaining.It was a sequence that got Northwestern back in the game. The Wildcats were successful most of the night with their deliberate pass-and-cut offense that would often take the shot clock down to the final seconds.Northwestern won the boards, despite the absence of the 6-8 Shurna, 31-20 and had 14 on the offensive end. Ohio State shot 57 percent for the game and Sullinger was 7 for 12 from the field.Shurna, who averages 19 points, sat on the bench in warmups with a boot on his left ankle that had been sprained earlier this season.The Buckeyes, meanwhile, have now matched the second longest winning streak in school history.In 2006-07 Ohio State also won 22 straight, counting tournament games, before losing in the NCAA championship game. The 1961-62 team was victorious in its first 22 games. The longest Buckeyes win streak was 32, spanning two seasons from 1959-60 (last five) to 1960-61 (first 27).