Ainge blasts Celtics' cavalier approach

Ainge blamed the starters, who combined for 21 points on 5-for-21 shooting after the break, for their lackadaisical second-half approach.

“It’s been a pattern that we have squandered leads against good teams in this league,’’ Ainge said yesterday. “I think the onus is on the starters. The good news is we are getting double-digit leads, but we are not doing a good enough job of finishing games.’’

The Celtics have consistently established big first-half leads, only to collapse in the third quarter. On Feb. 7 against Orlando, the Celtics were outscored, 36-11, in the third quarter and never recovered. The Cavaliers outscored the Celtics, 25-18, in the third, and Ainge said his starters are not bringing energy into the second half.

Ainge pointed out that Cleveland’s first four field goals of the third quarter were dunks or layups - an Anthony Parker dunk, Anderson Varejao and Mo Williams layups, and a LeBron James dunk. What’s more, eight of Cleveland 10 third-quarter field goals were inside of 7 feet.

“It’s been an issue, and the starters have to take the responsibility,’’ Ainge said. “They’ve been together, have experience, and it’s been a pattern the last month. We have to play with more urgency.’’

Lack of urgency was recognized as a problem months ago, but little has been done to rectify it. Said coach Doc Rivers following Thursday’s game: “There’s nothing I can do about [double-digit leads]. Obviously, I’d like to improve it. We’d like to be better. But we’re not right now, and we’ve just got to keep working on it. I know what we need to do. But one night it’ll be the defense, one night it’ll be the offense.’’

The Celtics took yesterday off and face the lowly Nets this afternoon at TD Garden. Paul Pierce has missed the last two games and Ainge said he was unsure whether his All-Star forward would play today or Tuesday against the Pistons.

The Celtics’ next major challenge comes March 14 in Cleveland.