Having fought through physical play in the paint that stopped him from dominating inside for most of the game, Sullinger scored seven crucial points in the final 3:36 to boost Ohio State to a 73-66 win over Gonzaga in the Consol Energy Center.
Sullinger, who made a basket off the glass over 7-foot center Robert Sacre to extend the Buckeyes' lead to five with 1:03 remaining, helped Ohio State advance to the NCAA Tournament's Sweet 16 for the third consecutive year.
The second-seeded Buckeyes (29-7) will play the winner of the Cincinnati-Florida State game in the East Regional semifinal on Thursday night in Boston.
"Down the stretch we wanted to get the ball in his hands," Ohio State coach Thad Matta said of Sullinger. "He's a winner. We'll ride that down the stretch."
Sullinger and Deshaun Thomas both led the Buckeyes with 18 points a piece and Aaron Craft had season-highs in points (17) and assists (10). Gary Bell Jr. led the seventh-seeded Bulldogs (26-6) with 18 points.
Ohio State led 52-42 with 14:22 remaining in the game, but Gonzaga switched to a zone defense to make one final run. The Buckeyes, who managed only 11 points in the next 12 minutes of the game, saw the score tied at 61 with 4:02 remaining in the contest when Elias Harris buried a three-pointer from the right corner.
Harris' make came after Sullinger was swatted by Sacre on the other end, but Ohio State's big man aggressively went right back to the basket before scoring a baseline bucket to give the Buckeyes a two-point lead with 3:36 remaining in the game.
"I don't care. It doesn't bother me when someone blocks my shot," Sullinger said. "It was a big time block (by Sacre), but I decided to make a move (on the next possession) and get off his body to eliminate his athletic ability."
The Buckeyes came up with a stop on the other end and Thomas made 1-of-2 free throws to extend his team's lead to 64-61 with 2:41 remaining in the game.
The Buckeyes came up with another defensive stop on the ensuing possession and Sullinger grabbed the rebound, but he missed the front end of the 1-and-1 that could have extended Ohio State's lead to two possessions.
Gonzaga point guard Kevin Pangos had a chance to tie the game with a wide-open look from the corner, but he misfired. Senior William Buford came down with the big rebound and Sullinger made the shot that put Ohio State out of the Bulldogs' reach.
"It's always about the next play," said Sullinger, who didn't let the missed free throw affect him. "You just have to keep playing hard and executing. If I would have focused on the past, it would have frustrated me and maybe I wouldn't have made that shot."
The story of the game was supposed to be how Sullinger matched up with Sacre. However, after playing only nine minutes of the first half while being hampered with foul trouble, it was about the supporting cast.
Ohio State faced a deficit as high as seven points at 27-20 with just under eight minutes to go in the first half when Sacre made a shot. The Buckeyes, however, out-scored the Bulldogs 19-10 for the remainder of the half to take a two-point lead into the locker room.
Thomas, who scored a career-high 31 points in Ohio State's NCAA Tournament-opening win over Loyola (Md.) Thursday, scored 10-straight points in the final 3:07 to aid the Buckeyes crucial rally.
Aaron Craft, who scored 10 of his points in the first half, has made an effort to look for his own shot more. Those efforts helped the Buckeyes prevent Gonzaga from creating a big lead heading into the break.
"It isn't my month – it is our month," Thomas said. "This was a complete team effort. We all came together to make the shots we needed to in order to stay in the game. It always hurts when Sullinger is out, but this team is more than just Jared."
Ohio State is now one win away from advancing past the Sweet 16 for the first time since the team went to the Final Four in 2006-07. The Buckeyes, now confident as ever, await their trip to the East Coast.
"We're good enough to make things happen," junior Evan Ravenel said. "It's onto the next phase of this tournament. I think we're ready."