Call it the Celtics' second-half snooze.
Once again, the Celtics led at halftime Tuesday night at the Garden, and once again they came out of the locker room in an offensive funk.
The second-half shooting woes that cost the Celtics the opener Saturday recurred in Game 2, costing them yet another potential win over the Knicks.
On the heels of scoring only 25 second-half points in their Game 1 loss, the Celtics managed just 23 points in the second half en route to an 87-71 loss.
Now down two games to none in this best-of-seven series, the Celtics know they need to figure out how to spark some life into their offense coming out of the half.
"I don't know what we're doing wrong in the third quarter," coach Doc Rivers said.
The Celtics led by six points at halftime after a well-balanced scoring assault in which seven players connected on 55.9 percent of their shots (19-for-34). It was an all-around feel-good half, and the players knew they had to keep it up in order to go home with the series tied at 1.
"During halftime, we said let's not play like we did last game," guard Avery Bradley said, "and we came out and we did the same thing. We're beating ourselves over our head. We definitely don't want to continue this trend of coming out in the second half and not playing hard."
Just how cold were the Celtics to start the second half Tuesday night?
They hit only one field goal -- a layup by Paul Pierce -- in the first 7:45 of the third quarter, and the Knicks took advantage. Behind nine points by Carmelo Anthony, the Knicks went on a 24-4 run to take a 66-52 lead with 4:15 left in the quarter.
"I just really didn't think we came out with the same mentality that we had in the first half, and I don't know why," Rivers said. "I need to find that out in the next two days."
The Celtics scored only 11 points and shot 4-for-18 in the third quarter, and that was the reason the Knicks turned their six-point halftime deficit into a 15-point lead.
After the Knicks grabbed the lead at 52-50, Rivers called timeout and lit into his team, screaming so emphatically that it looked as if he was trying to will life back into his team's suddenly static offense.
It didn't work. The Celtics' next field goal wasn't until Kevin Garnett hit an open jumper some four minutes later. By then, the Knicks' lead had grown to double digits, 66-54, and they never looked back.
"We had a chance to really come out and make a statement in the third quarter and we didn't do that," Pierce said. "We did the opposite."