COLUMBUS, Ohio -- It wasn't Ohio State coach Thad Matta's idea to drill his players on defense this week.
It was theirs.
David Lighty scored 18 points and Ohio State wasn't tested in its first game as No. 1, rolling over Iowa 70-48 on Wednesday night.
"It was funny, in the film session on Monday they kind of said, 'Hey, looking at the scores we've given up, we can play better [defensively] than this,' " Matta said. "So I told them before the game, 'You're the ones who said that, now we've got to go out and back it up.' I thought they did that."
The Buckeyes (19-0, 6-0 Big Ten) improved to 60-4 when ranked first in The Associated Press poll.
Shaky at times on offense, they set the tone and tenor with their defense right out of the box.
"They got us off to a slow start," Iowa coach Fran McCaffery said. "You go on the road, you play a team of this caliber, you need to get off to a good start offensively. You need some buckets, you need to settle down, you need to get some type of flow. We never had a flow. Every basket we got in the first half was a struggle."
Up 40-23 at halftime, the Buckeyes reeled off seven of the first nine points of the second half to push the lead to 22. The outcome wasn't in doubt the rest of the way.
William Buford had 15 points and Jared Sullinger added 13 for the Buckeyes, topping the polls for the first time since the final three weeks of the 2006-07 regular season. That season's team went to the national championship game, losing to defending champion Florida and finishing with a 35-4 record.
Lighty said nothing changed for the Buckeyes by moving up a spot in the rankings to replace Duke, which had been on top all season.
"From our point of view, nothing was really different at all," he said. "We approached the game the same way, practiced the same way -- just worrying about us and getting better."
Four players had four assists apiece for the Buckeyes. Aaron Craft set an Ohio State freshman record with seven steals, tying for the second-most ever at the school behind Troy Taylor's eight against Saint Joseph's in 1983.
"That's a team stat," he said. "Everyone's in the gaps and putting pressure on the ball. I appreciate that I just happened to get that stat tonight."
The Buckeyes are off to the third-best start in the school's 112 seasons, behind only the 1960-61 team (27-0), and the 1961-62 team (22-0). Both of those teams also went to the NCAA title game, losing to Cincinnati.
The Buckeyes did have a season-high 20 turnovers, hardly the way to tune up for a big test on Saturday at Illinois (No. 22 ESPN/USA Today, No. T-23 AP) .
That's an area that will require work. In the coming weeks, any problem area will be revealed. Seven of Ohio State's next nine opponents are ranked this week.
"You can only play one team at one time," Lighty said. "Whoever's next, that's who we have to worry about. It's going to be tough on the road, wherever you play, especially in the Big Ten. So we have to have our minds right."
The Hawkeyes fell to 2-19 against teams ranked No. 1.
Just 15 days ago, Iowa gave the Buckeyes all they could handle before falling 73-68 in Iowa City. Not this time.
"The defense made a big difference for us obviously, because we didn't give them as many easy baskets as we did up there," Matta said. "We allowed them to gain some momentum on us a couple of weeks ago. In the game tonight, we set the tone of, 'Hey, we're here to defend tonight.' And that was a big thing going into the game."
Dallas Lauderdale, a starter with diminishing minutes, set the tone early for the Buckeyes. He had seven points -- he came in averaging 4.5 -- in the opening 5:37 as Ohio State opened a 12-4 lead.
After that, the Buckeyes got going in transition. Buford, who had 11 points in the first half, and Lighty, who added eight, hurried the ball down the court or whipped it around the perimeter for easy baskets.
"When you look at their shooting percentages in the first half, 54 [from the field] and 46 [on 3s], it's hard to win against a team like this," McCaffery said. "Obviously, it's not the only time they've done this. They've got really good shooters and a great low-post game."
Maryland point guard Melo Trimble, considered a lock to leave the program before struggling in the second half last season, has withdrawn from the NBA draft and will return for his junior season.
Louisville's Chinanu Onuaku, who recently underwent a medical procedure to correct a heart rhythm issue detected during the combine, will keep his name in the NBA draft pool.
Andrew White III will return to the Nebraska men's basketball team next season after removing his name from the NBA draft.