TORONTO -- Toronto guard Greivis Vasquez had a hard time getting any rest Wednesday night after the Raptors blew a huge lead in a pivotal Game 5 win over Brooklyn.

He kept thinking about the mental mistakes, missed assignments and sloppy play that nearly cost them the game.

"I couldn't sleep. That was disgusting," Vasquez said Thursday. "That was ugly -- a couple turnovers, a couple fouls, a couple (baskets and fouls) for them. It wasn't us."

Toronto saw its 26-point lead disintegrate as the Nets put up a whopping 44 points in the fourth quarter Wednesday night. It took a late basket from Raptors guard Kyle Lowry and four key free throws by DeMar DeRozan to preserve a 115-113 victory.

With the narrow victory, the Raptors moved a win away from locking up a berth in the second round of the NBA playoffs. But the fact they came perilously close to what would have been an epic loss was hard to ignore.

The Raptors held a closed-door practice session Thursday afternoon at Air Canada Centre and emerged confident that the blip was behind them. They'll try to close out the Nets on the road in Game 6 on Friday night.

"The mental things going into each game -- that was the lesson today, more so than thinking about closing out," Casey said. "We've got to again continue to improve and not make some of the mistakes we've been making."

Toronto's stars came up big before a raucous home crowd on Wednesday. Lowry had a 36-point night and DeRozan added 23 points and six rebounds.

Casey noted that it was one of DeRozan's strongest games of the series, adding he did a nice job getting out of traps so his teammates could attack the weak side of the floor. He also praised Lowry, who played one of his best games as a Raptor.

"Kyle's play -- it carried us," Casey said. "Without his offence, we would have really struggled. But he ignited everybody and got us free flowing up and down the floor."

Toronto led 62-44 at the half and had a comfortable 91-69 edge after three quarters.

However, on three occasions in the fourth quarter, the Raptors committed fouls beyond the arc to set up rare four-point play situations. Blown coverages also let Brooklyn's Joe Johnson heat up, and he scored 26 of his 30 points in the second half.

"You can't leave the best shooters on the court wide open," Vasquez said. "That's another mental mistake. So we'll get better, but we've got to be hard on ourselves because we can't be happy because we won three games.

"We've got to understand that we want more and we do."

A couple of late brain cramps made it even more of a nailbiter. Forward Amir Johnson fouled Alan Anderson for a four-point play with 9.7 seconds left.

"It was one of those bone-headed plays that you just can't do," Johnson said.

In addition, the Nets weren't boxed out properly after a missed free throw with 4.9 seconds left. Toronto got lucky that an errant pass prevented a potential game-winning shot attempt.

"The positive thing about the whole thing is that we won," Casey said. "We found a way to win with all those mistakes. With every mistake we made we still found a way to win, which is a great positive for a young team."

Both teams have held big leads throughout the series but the point difference at the finish has always been single digits. If Game 7 is necessary, it will be played Sunday in Toronto.

Vasquez said the Raptors plan to play angry on Friday night at Barclays Center, predicting it will be "another street fight."

"We're very confident," he said. "We're not going to underestimate them. But we're going to go there with a mentality like we're going to fight and we're going to try to do whatever it takes to get this win.

"We're very humble but at the same time we're very hungry."