Boston Celtics coach Brad Stevens couldn’t have enjoyed what he was seeing from his team as the Toronto Raptors ripped off a monster fourth-quarter run, but Stevens resisted the urge to call a timeout, seemingly intent on seeing if his team could steady itself as the game slipped from its grasp.

One of Boston’s biggest weaknesses last season was an inability to respond to adversity. Having posted two 20-point victories to start the exhibition season, the Celtics hadn’t really encountered much white-knuckle time before Friday’s game in Toronto. But there was Stevens, stoic as always, quietly observing his team as the Air Canada Centre rocked as if the calendar read early May, not early October.

The Raptors outscored Boston by 18 points over a six-minute span to emerge with a 116-109 triumph.

“When you have guys that are competitive, sometimes they try to do too much and it snowballs. That’s what happened,” said Stevens, referencing how a Boston team that scorched the field most of the night went ice cold as Toronto rallied. Boston shot 49.3 percent overall, but was 1-of-7 (14.3 percent) and turned the ball over five times during Toronto’s fourth-quarter outburst.

“We have to get better at that,” Stevens said. “We talked about being able to respond in any situation, so that was something new for this team. Hopefully we have that again, as far as having to respond again in the preseason.”

The Celtics played a whopping 49 regular-season games last year that were within five points in the final five minutes. That was tied for the fourth-most in the league and Boston was a cringe-worthy 15-34 in those games, its .306 winning percentage the second-worst mark in the NBA (behind only Milwaukee at .250).

If the Celtics are to take a step forward this season, regardless of the size …read more