In the waning seconds of Tuesday night's National Invitation Tournament semifinal, North Carolina junior Will Graves dove for a loose ball - inadvertently tripping Rhode Island's Lamonte Ulmer, who coughed up possession and sealed the Tar Heels' overtime victory.

Whether a whistle should have been blown remains up for debate. But just the fact that Graves was scrambling on the floor at all - showing the extra effort that had been missing all too often from the Tar Heels this season - shows why UNC (20-16) has won four straight games and will play Dayton (24-12) in the NIT title game tonight.

"I don't know that it's disappeared," coach Roy Williams said of his team's propensity to take plays off, "but it is a heck of a lot better. ... I do believe we are playing much harder, the intensity is there, the concentration is there."

It's been a long, frustrating time in coming.

All too often during UNC's slide from top-10 team to NIT bubble squad, Tar Heels players would point to a lack of focus or intensity in trying to describe why they played lackadaisical defense, took bad shots or didn't scramble to grab rebounds or loose balls.

Williams, who has said that he had to coach effort this season more than any other time in his career, first started seeing a new urgency during the Tar Heels' first-round NIT victory against William & Mary at Carmichael Arena. Perhaps they felt like the pressure was off, or perhaps they didn't want to embarrass themselves in the historic gym, but "the intensity that night, the enthusiasm - Deon [Thompson] with the big dive in front of the scorer's table, and that whole bit - I do believe it started there, and it's continued."

Things haven't been perfect; Williams, for example, benched four of his five starters for roughly eight minutes in the first half of the second-round Mississippi State win because they weren't playing like they wanted to be there.

But players admit that even a month ago, they might not have been able to pull out an ugly win like the one against URI - when they shot less than 35 percent, committed 17 turnovers but scrapped back to force overtime.

They then sealed the game with a game-saving turnover (even if it could have been called a foul).

"It's a do-or-die situation - especially now, out here," point guard Larry Drew II said. "We didn't come out here to lay down and give the game away. We're all going to play hard, we're all going to make sure we didn't leave anything on the court."

But why did it take so long? Whatever the outcome tonight, that will probably remain the biggest rub of the season.

Williams said his staff didn't change its coaching style entering the NIT.

"We just continued to emphasize [effort], and push and push and push. I think they absorbed it ... finally. But they've also taken it to the court. I kept saying, 'I've got to find a way to get them to do that.' And I still don't know what we did, except they do have 'it' a lot better now."

Which is a good thing, considering its championship opponent at Madison Square Garden.

The Flyers, who are making their 22nd NIT appearance, are a fast team that likes to substitute; facing the athleticism of Chris Wright (13.7 ppg, 7.2 rpg), Chris Johnson (11.8, 6.9) and Marcus Johnson (9.0, 3.3), Williams said, is impossible to simulate.

Thompson, though, said that no matter what UNC sees from Dayton, the most important thing is that he finally knows what he can expect from his team: an urgency unlike anything he saw during the regular season.

"It definitely is a bright spot to see guys continue to fight, to continue to rally, and get ourselves here," Thompson said. "... We're playing for a championship, and we've come this far - and there's a feeling on this team that we didn't come this far to lose. So I think you're going to get guys hustling, giving effort, diving for loose balls and things like that."