Hard to say when statistics become a trend. Statistics show that since the start of the 2007 season - 29 games, from Georgia Tech (the ‘07 opener) to last week’s escape at Purdue - the Notre Dame football team has been outscored in the second half 16 times.

The Irish have lost all but two of those games - Stanford last year and Purdue last week.

Not enough adjustments at halftime? Too many? Lack of conditioning? Lack of killer instinct?

So many factors can play into the situation that it’s hard to pin a reason down. For instance, at halftime last week, Irish coach Charlie Weis had to deal with a gimpy quarterback Jimmy Clausen as well as the problems posed by the Boilermakers.

He tried to get by with sophomore backup Dayne Crist at the controls in the second half, but had to turn to Clausen for the game-winning drive.

“Normally, you’ve got your game plan,” Weis said of the halftime adjustments. “Now, some of the stuff you game-planned for just doesn’t look very good against what they’re doing. Other things look real good, and you haven’t gone to the well and taken another drink (overusing plays).

“You try to look at what looks good against what they’re doing, and let’s go back and try to do that again.”

What’s the temptation to try to think too much during that brief respite?

“I’m a very objective person,” Weis said. “Here’s what they’re doing, here’s what we’re doing. This doesn’t look any good. I might think some stuff I had was just great, and it might look like garbage, so at halftime I just throw them out.”

Adjustments made. Time to execute.

Over the past two seasons, learning how to win in the second half was a challenge. Losing leads was a tough rut to escape.

“I think you gain something from every game,” Weis said. “What you didn’t gain by putting Purdue away when you’re up 17-7 ... you gained by having to run a two-minute drive at the end to win the game.

“Part of when you really, truly turn a corner, you put yourself in a position (to win), throw out the extenuating circumstances, and try to pull away. You never want to be playing in a game where you are playing to the last minute. That might be good for TV, but it’s not good for programs that want to move forward.”

Pat Haden knows about TV. He’s been NBC’s analyst for Irish football telecasts for 11 seasons. He also knows what’s good for a program. Haden was a quarterback at Southern Cal before embarking on a six-year NFL career.

He’s watched the Notre Dame program evolve under Weis and sees the second-half problems as more of a blip than a blight.

Haden refuses to lump 2007 and ‘08 with this season for one reason - Clausen.

“You can’t compare those two years with this one,” Haden said. “Jimmy makes a big difference.”

Rather than looking at the Purdue game as a negative because the Irish were outscored 14-7 in the final 30 minutes, he sees Clausen’s game-winning drive - on a bad hoof - as the real positive.

“It’s belief and confidence that win,” Haden said. “It sounds so simplistic. What you need is a quarterback that’s been there, done that. That’s Jimmy Clausen this year.

“(The other players) have to be able to look the quarterback in the eye and believe we’re going to win. ‘I’ll do my job and let the quarterback win.’ Once he’s able to do that once or twice, it becomes the ethos of the team.”

“The biggest thing for us is that we’ve been there before,” Clausen said of the turnaround. “We’ve had to deal with adversity - whether it’s first half, second half or the whole year. Every time, at least the offense, every time we get the ball we expect to score.”

That’s the reason Haden didn’t take the loss to Michigan as that much of a negative, either. Coming back from 11-point deficits a couple times showed the fight and the spunk of the Irish offense.

“Clausen’s playing as well as anyone in the country - (Oklahoma’s) Sam Bradford, (Texas’) Colt McCoy, anyone,” Haden said. “At the start of the season, I didn’t know what to believe. But Jimmy carries himself differently than he ever did. You see kids grow up. At our first meeting, I noticed right away that he carried himself differently.”

“It’s different coming from high school into college,” Clausen said. “You think you’re good, you think you can step right in and play, but it’s something that’s extremely tough. It’s taken me two, three years to get to this point. I’m handling myself like when I was a veteran in high school.

“I know everything now. I know the offense. I know how to handle myself on and off the field, handle my teammates, be a leader and a captain of the team. It’s something I’ve had to evolve to.”

Trends, like beauty, can be in the eye of the beholder. Is the frequency of the second-half shortcomings a problem? Or, is the recent Irish resiliency cause for celebration and hope for the immediate future?

“College football is never one straight line,” Haden said. “A lot goes into it.”

Stay tuned.