COLUMBUS - Ready or not, the Ohio State Buckeyes play their first Big Ten game on Saturday against Northwestern.

Four games and four victories into defending their national title, they have shown flashes of brilliance along with moments of unvarnished ineptitude. The rest of the time, the No. 4 Buckeyes have appeared to be a very pedestrian team on offense instead of the powerhouse many expected.

Some of the statistics are mediocre. Then again, it's hard to improve on a perfect record.

''Ohio State is a great football team. Ohio State knows how to win. Ohio State has 18 wins in a row,'' Bowling Green quarterback Josh Harris said after safety Will Allen picked off his last-second pass to cap yet another 24-17 skin-of-the-teeth win for the Buckeyes on Saturday. ''You can see why. They have each other's back. They find ways to win the game. That's the mark of a great football team.''

The Buckeyes host Northwestern (2-2) on Saturday in the first step of their defense of a 15th outright Big Ten title. The game ends a five-game homestand at Ohio Stadium. They then get a week off before their first road game at Wisconsin.

Close games have caused some serious palpitations for Ohio State's fans, but like Indiana Jones - and not the Indiana Hoosiers - the Buckeyes always seem to escape at the end. Nine of their last 11 wins have been decided by a touchdown or less.

''Bowling Green played us tough. One bad series and they were back in the game,'' said Allen, savior of the past three games with big plays. ''This is the seniors' responsibility to get the team to play good for the whole game.''

There are some encouraging signs. The Buckeyes finally got their running attack going after struggling to get positive yardage in the first three games. Just like last year's 14-0 season, the defense has given up yardage at times but never when the game is hanging in the balance. Linebacker A.J. Hawk is off to a monster start. Kicker Mike Nugent and punter B.J. Sander have been dependable.

Mostly, the Buckeyes' timing has been impeccable.

''We made the plays when it counted,'' defensive end Simon Fraser said. ''Our fourth quarter is a little lackadaisical. We need to study why that's happening.''

Ohio State has churned ahead despite the loss of leading rusher Maurice Clarett - suspended for the year for violating NCAA rules - and quarterback Craig Krenzel. Krenzel watched the Bowling Green game from the sideline, resting a hyperextended right elbow. He may not be available for the Big Ten opener, with Scott McMullen again filling in.

The biggest strength is that opposing teams have run into a brick wall when they've attempted to run the ball. Ohio State has surrendered less than a yard per carry, giving up 96 yards on 103 rushing attempts.

''I didn't anticipate being able to run the ball,'' Bowling Green coach Gregg Brandon said after the Falcons mustered just 40 net yards on 23 carries. ''No one has run the ball against them.''

Still, coach Jim Tressel remains perplexed by a series of ongoing problems. The Buckeyes had three more turnovers on Saturday and now have 12 for the year - they had only 17 in a 14-game marathon season in 2002.

Asked the cause of all the turnovers, Tressel said, ''I don't know. If I knew, hopefully I could solve it.''

The offensive line continues to be a nagging problem, with Krenzel and McMullen taking some frightful hits and rushers frequently running into defenders in the backfield. After piling up penalties in record numbers for the past two games, the Buckeyes were flagged just three times against the Falcons.

''The running game was better and the passing game was OK,'' said wide receiver Michael Jenkins. ''We've still got a lot of growing to do.''

That might be the bottom line. Since every starter but Clarett was back on offense, many assumed points and yardage wouldn't be a problem. They have been. It's not as if the Buckeyes don't recognize that.

''We must get more consistent,'' said tailback Lydell Ross, who ran for two scores against Bowling Green. ''We have to drive down the field every time - and I mean every time - and start making big plays. That's what we need.''