Deron Williams scored 29 points Brook Lopez  added 21 as the Brooklyn Nets beat the Celtics , 101-93, Wednesday night at TD Garden. Paul Pierce  had 23 to lead the Celtics, who fell to 40-38 on the season. In his second game back from an inflamed left ankle, Kevin Garnett  rebounded from a 1-for-6 first half to finish with 11 points and eight rebounds in 28 minutes.
With the loss, the Celtics appear locked in for the seventh-seed and a first-round match up with the Knicks as the sixth-seed Hawks beat the Sixers in Philadelphia to move two games ahead of the Celtics in the loss column. With the Bucks’ loss in Orlando, Boston is still three games up in the loss column on eighth place Milwaukee. The Celtics and Bucks each have four games left.
The Nets  improved to 46-32 and are all but locked in at the No. 4 seed heading into the playoffs.
In a game the Celtics showed little defensive intensity, the first quarter started out with great promise. The Celtics shot out to a 17-9 lead, highlighted by a dunk from Brandon Bass over Brook Lopez with six minutes left in the opening quarter . Brandon Bass  led the Celtics with eight points in the first quarter but the Nets outscored the Celtics, 13-4, in the last six minutes of the quarter to take a 22-21 lead after 12 minutes. Boston finished the first quarter shooting just 9-of-23 from the field.
Boston’s defense in the second quarter was leaky, as the Nets made two-thirds of their shots from the floor, finishing the period 12-of-18. Williams had 11 of his 27 points in the quarter as the Nets took command of the game with a 53-43 halftime lead.
Another telling sign of how the Celtics were dominated on the inside was the lack of free throws. With Boston’s offensive generated almost exclusively from the perimeter, the Celtics didn’t get to the free throw line until 8:22 left in the third quarter, when Pierce hit a free throw to complete a 3-point play.
There were signs of life in the third quarter as Jeff Green  drilled a three with 4:29 left to cut Brooklyn’s lead to 11, 68-57. Then, Shav Randolph drew a charge on Brook Lopez. After two Pierce free throws cut the lead under 10, Lopez hit a five-foot bank shot to stem the Boston tide.
Pierce’s three with 1:09 left drew Boston within 10, 77-67, but as was the case throughout, the Nets came right back and responded with a layup from Deron Williams to put Brooklyn back ahead by 12. Pierce finished the third quarter with 13 points as Boston entered the fourth down 79-69.
The Celtics trailed 89-77 when Green took the ball to the basket for a layup and was fouled. His free throw cut the deficit under 10 again, 89-80, with 7:15 left. The Celtics were within eight, 90-82, when Williams finally connected on a 3-pointer. He had missed his previous five attempts from long range. The three with 5:17 left put Brooklyn up, 93-82, and sent many in the crowd to the exits. The Williams basket also sparked a 11-0 run that put the game away.
The Celtics are off Thursday before hitting the road for games in Miami and Orlando Friday and Saturday nights. The Celtics conclude their regular season schedule next week with a home game against the Pacers next Tuesday and a road game in Toronto next Wednesday.
For more from Mike Petraglia and Ben Rohrbach from the Garden, visit the Celtics team page at weei.com/celtics .