Reeling from an 18-3 run by the Brooklyn Nets to start the second half, Toronto was down 10 points against a team looking to win its season-high sixth straight game. But rather than rollover, the Raptors fought back, showed what their head coach called newfound "mental toughness" and coasted to a comfortable 96-80 victory before a sellout crowd of 19,800 at Air Canada Centre.
"I think our guys showed mental toughness and won a slug out game which I don't know if we could have won a few months ago, no less last year," Casey said of the Raptors second straight win, which gave them a four-game lead over the Nets atop the NBA's Atlantic Division.
"It's a testament to our guys' mental growth and mental toughness to win a game like that."
After Brooklyn built its biggest lead of the night at 10 points at the midway mark of the third quarter, the Raptors went on a 28-5 run over the next 10:33 to secure their seventh win in their last nine games.
After 35 games, the Raptors are 18-17.
At this point last season, Toronto was 13-22.
"Guys are growing up," Casey said when asked to explain the difference in the Raptors this season from last. "They're getting tired of me preaching physicality, don't get knocked down in a street fight."
Leading the way for the Raptors was DeMar DeRozan, who poured in a game-high 26 points.
Terrence Ross added 14 points for the Raptors while Patrick Patterson had 14 points and 12 rebounds.
The Raptors took a 47-42 lead into the halftime break on the strength of 11 first-half points from Ross, who hit half of Toronto's six three-pointers in the opening 24 minutes.
Toronto, which shot an anaemic 38.6 per cent from the field in the first half, led by as many as 13 points in the second quarter but the Nets continued to fight back.
But then the visitors took over the game — and silenced the boisterous crowd celebrating Drake Night in honour of the hometown rapper and Raptors' global ambassador — before Toronto regained control.
After Brooklyn's Shaun Livingston hit a six-foot jump shot to restore the Nets' 10-point lead with 4:54 to go in the quarter, the Raptors scored 16 of the final 18 points to close it out.
DeRozan scored the final seven points of the third quarter, capping it with a 25-foot three-pointer.
The Raptors then went on a 10-1 run to open the fourth quarter and put the game away.
"We stayed patient. We knew they were going to make a run, especially in the second half," DeRozan said. "We stayed disciplined, understood we had to get stops, rebound the ball and push it.
"If I've got to step up to win, I'm going to do as much as I can."
In addition to praising the "big time" performance by DeRozan, Casey also lauded the contributions of Patterson and John Salmons — who came over as part of the trade for Rudy Gay — to the team's toughness.
The Raptors win ended a five-game win streak for Brooklyn (15-22).
"Well, it was an important game," said Toronto guard Kyle Lowry, who had 12 points. "Every game we play is important. We can't take any game for granted.
"It was really important with them being a divisional team and them playing really well now. We needed to get this win for our confidence."
The Raptors close out their three-game homestand against the Milwaukee Bucks on Monday night.