Transition breakdowns can hurt Celtics

Boston Celtics coach Doc Rivers preaches transition defense, firmly believing that if his team can get five players back, forcing its opponent to operate in a half-court set, Boston has a decided advantage based on its defensive talents.

General statistics support this. The Celtics sit atop the league in defensive efficiency (points allowed per 100 possessions) at 96.7, nearly seven points below the NBA average.

The Celtics aid their defensive cause in two key ways: (1) They are shooting a league-best 50.1 percent, meaning teams can't run against them as often because there aren't as many rebounds to collect, and (2) Boston's philosophy to de-emphasize offensive rebounds with the idea of allowing perimeter players to drop back on defense (the Celtics are last in the league by grabbing a mere 21.4 percent of available offensive rebounds).

According to Synergy Sports Technology, the Celtics rank third in the NBA in both defensive efficiency in the half-court set (84.1 points per 100 possessions) and field goal defense in the half court (41.3 percent). But in transition, those numbers skyrocket to a defensive efficiency of 112.4, while opponents shoot 57.3 percent (15th in the NBA).

And the Celtics make a point of limiting their opponents' transition opportunities. They have allowed only 241 field goal attempts in transition, third-fewest in the NBA entering Monday's games.

But here's the catch: Boston can be careless with the ball. The Celtics are committing 13.7 turnovers per game, which is in the middle of the pack. But their turnover rate (14.2 percent per 100 possessions) ranks in the bottom third because of the team's slower pace of play.

Those turnovers give opponents rare opportunities to attack the Celtics when they're not set, and that's where the transition defense that Rivers preaches comes into play.

Not surprisingly, the 23-5 Celtics have been pretty good this season limiting their opponents' fast-break points. In fact, Boston is outscoring its opponents on the break by an average of four points per game.

But when there are lapses, it bites the Celtics. That's what happened in Saturday's loss to Orlando, when the Magic finished with 20 fast-break points (nearly double what Boston typically allows). Orlando generated nearly a quarter of its points in transition (while shooting just 39.5 percent for the game).

"For us, it's all about transition defense," Rivers said last week before a game against the Philadelphia 76ers. "Honestly, we talked about it and it's an area of slippage for us right now that we have to correct. If you don't correct it, it could be a long night."

The young, athletic 76ers generated a whopping 22 fast-break points during a Dec. 9 meeting (the second-highest output against Boston this season) and the Celtics needed a buzzer-beating alley-oop from Rajon Rondo to Kevin Garnett to escape with a 102-101 triumph.

Rivers knew last week's rematch in Boston would offer a chance to gauge his team's transition defense.

"In some ways, you'd rather not play [the 76ers] because that's an area we're struggling in," Rivers said before the game. "In the other way, actually, you want to play them because it's an area we have to get better at. We were great at it, and we've kind of slipped."

Philadelphia, which was heavy legged on the second night of a back-to-back and coming off a 45-point thrashing by the Bulls the night before, generated a mere seven fast-break points. Boston aided its cause by only committing 10 turnovers.

Asked about the key to his team's success after the game, Rivers smiled and said, "We got back."

Take away that ugly 22-point allowance in the first Philadelphia meeting, and the Celtics allowed only 9.5 fast-break points per game during their 14-game winning streak.

Keep an eye on fast-break points when the Celtics visit the Indiana Pacers on Tuesday night at Conseco Fieldhouse. In a meeting last week (a 99-88 Celtics win), Boston outscored Indiana 23-14 in that category. Not surprisingly, Pacers forward Mike Dunleavy quickly cited that as the reason for his team's demise.

"In the first half, we just gave up too many transition points," Dunleavy said. "The second half, too, our half-court defense was doing pretty well for us. But just in transition, [the Celtics] were getting too much easy stuff and that's the difference in it being a close game and us being up by 10."

Rivers would nod in approval. If the Celtics had played better transition defense Saturday, they might still have their lengthy winning streak. As they look to start another one, they need to eliminate Saturday's slippage.

Chris Forsberg is the Celtics reporter for ESPNBoston.com. Follow him on Twitter.