One glance at the breakdown of second-chance points allowed by the Boston Celtics in recent games seems to reflect a glaring reason for their struggles. The Celtics were outscored on second-chance points, 49-15, during a three-game home losing streak last week and that statistic didn't exactly improve Friday when the Portland Trail Blazers boasted a 22-8 advantage in Boston's overtime triumph.

What's more, opponents owned a 130-106 advantage in total rebounds during that three-game losing streak to Atlanta, Dallas, and Chicago, with a 32-19 advantage on the offensive glass.

Asked about those troubles this past weekend, Celtics coach Doc Rivers didn't seem overly concerned. In fact, he suggested the lopsided numbers actually show how well the Celtics are playing defense this season.

"We're holding teams to 41, 42, 43 percent shooting [from the field], so clearly there's more offensive rebound opportunities," said Rivers, whose own team is shooting an NBA-best 48.7 percent, while limiting opponents to 44.3 percent (sixth in the NBA). "If we can get defensive rebounds, we can shoot 60 percent, because we can run. When teams are scoring and getting offensive rebounds, that slows the game down and takes us out of our break."

The Celtics are 28th overall in total rebounds, averaging 38.97 boards, while their opponents are only marginally better at 39.48 rebounds per game (minus-0.51 differential, 21st in the league), the Celtics are generating two fewer offensive rebounds per game than their opponents.

Rivers noted that the Celtics don't put a heavy emphasis on generating their own offensive boards. He instructs his guards to fall back immediately upon shot release, while the bigs have the freedom to crash at their discretion. The Celtics have generated 20 or more second-chance points just once this year (Dec. 14 vs. Memphis) and haven't scaled more than 16 points outside of that visit to Memphis, where Boston boasted a 20-13 edge over the Grizzlies.

It's worth noting that, when the Celtics were most successful, including at the start of the season, opposing teams rarely generated higher totals in second-chance points. Opponents scored more than 10 second-chance points only once during a 6-0 start to the 2009-10 campaign.

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