The Associated Pressw

COLUMBUS - Ohio State's stunning upset of No. 21 Purdue could start a trend or it might just be a peak leading to another precipitous fall.

It takes more than one game to make a turnaround, and no one knows that more than the Buckeyes' Jim O'Brien, who has weathered 22 seasons as a college head coach.

So while O'Brien remains hopeful that his team has turned a corner, he also is hesitant to jump to conclusions based on the 65-59 victory over the Boilermakers on Saturday.

''Prior to that game, whenever things started to turn against us we really didn't respond in a favorable fashion,'' O'Brien said. ''If this is a sign, hopefully, of some maturity and that we are getting better, then that's a good thing. But we really will not know that until we play a few more games.''

The next gut check for the Buckeyes (10-10, 2-5 Big Ten) comes Wednesday night at home against Northwestern (8-10, 3-4).

Historically, the Wildcats are just a speed bump for Ohio State. They've lost the last nine meetings regardless of location and haven't left Columbus with a win since 1977 - a string of 24 consecutive defeats.

Then again, this is not a typical season. Northwestern has made inroads as it has grown accustomed to fourth-year coach Bill Carmody's backdoor-layup-and-3-pointer offense. The Wildcats opened the Big Ten with a nine-point win at Iowa and a 10-point win over in-state rival Illinois, serving notice that these are not the Mildcats of old.

No one is taking the Wildcats lightly these days. That goes double for an Ohio State team that lost three consecutive games by a combined 34 points before vanquishing Purdue.

''They have better players, particularly the guys who have been through (their system) for a couple of years,'' O'Brien said. ''Jitim Young is establishing himself as one of the better guards in the conference.''

Young is averaging 18.5 points a game with 6-foot-8 forward Vedran Vukusic scoring 14 a game.

Like O'Brien, Carmody is withholding judgment on his team until it has performed over the long haul.

''I'm a little pessimistic by nature,'' Carmody said. ''We're going through some stretches where we're playing pretty well then at other times we're just very average. The ups and downs of this are unbelievable. I guess I'm feeling a little bit better just because we're winning a couple of games and that's better than six weeks ago or two months ago.''

Carmody doesn't really know which Ohio State will show up - the one that displayed little perseverance and almost no cohesion early in January, or the tough and scrappy Buckeyes in West Lafayette.

''They've been up and down a little bit but they didn't play that way the other day,'' Carmody said. ''They jumped right out and it was like 16-3. Then they went down three or four and were tough enough to hang in there and win on the road.''

As the losses mounted over the last two months, the Buckeyes lost their confidence. It remains to be seen if they regained it in two halves.

''The one thing I'm hoping is we get a little shot of confidence so that when we get to some of these other games coming up we'll feel a little bit better about ourselves and at least we'll have a feeling that when things start to turn against us that it's not the end of the world,'' O'Brien said. ''One of the real key things of our game at Purdue was not so much that we got off to a great start but that once we lost the lead we were still able to keep our composure and come back and win the game on the road.''

In their last home game, a 69-57 loss to No. 17 Wisconsin last Wednesday, the Buckeyes were manhandled inside and out, shot poorly and couldn't muster a play when they needed one the most.

After the game, four assistant coaches confronted a teenage fan who was holding a sign disparaging O'Brien. O'Brien said that confrontation had nothing to do with his players' solid game three days later.

''I never even talked to them about it,'' O'Brien said. ''I did talk to them about making sure that we have to stay together when you start losing games and there becomes a little unrest.''