DALLAS (AP) Harrison Barnes scored 24 points and the last-place Dallas Mavericks knocked off a title contender for the second straight night, beating LeBron James and the Cleveland Cavaliers 104-97 on Monday.
Wesley Matthews had 21, and rookie point guard Yogi Ferrell scored a career-high 19 in the second game of a 10-day contract, a night after hitting two key free throws in the final seconds of a win at Southwest Division-leading San Antonio.
James had 23 points and Kyrie Irving scored 18 - but just one between them in the fourth quarter - for the defending champs, who were without fellow All-Star Kevin Love because of recurring back spasms.
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The Cavs dropped to 7-8 in January. The loss also trimmed Cleveland's lead for the top spot in the Eastern Conference to 2 1/2 games over Boston.
CELTICS 113, PISTONS 109
BOSTON (AP) - Isaiah Thomas scored 24 of his 41 points in the fourth quarter, and the Celtics extended their winning streak to four games.
Jae Crowder added 21 points and Al Horford scored 13 for Boston, which had to rally after Detroit surged midway through the fourth quarter and the teams traded the lead.
Andre Drummond had 28 points and pulled down 22 rebounds for the Pistons, who outscored Boston 60-38 in the paint and outrebounded the Celtics 51-44. Kentavious Caldwell-Pope added 18 points for Detroit, which lost its third straight.
Thomas extended his run of games with at least 20 points to 32 in a row. He carried Boston down the stretch, making nine free throws in the fourth quarter while going 15 for 15 from the line.
HEAT 104, NETS 96
MIAMI (AP) - Goran Dragic scored 20 points, Dion Waiters added 19 and the Heat pushed the NBA's longest current winning streak to eight games.
James Johnson had 17, Rodney McGruder scored 13 and Hassan Whiteside added 12 for Miami. Waiters and Dragic combined to hand out 17 assists for the Heat, who took the lead for good with a 17-0 run late in the first half.
Miami outscored Brooklyn 33-12 from 3-point range.
Bojan Bogdanovic scored 16 points for Brooklyn (9-39), which has lost six straight and 17 of its last 18.
76ERS 122, KINGS 119
PHILADELPHIA (AP) - Robert Covington had 23 points and 10 rebounds to rally Philadelphia to the victory.
The Sixers overcame 46 points from DeMarcus Cousins and won again without injured center Joel Embiid, who sat out with a left knee contusion. He also will not travel with the Sixers for road games later this week against Dallas and San Antonio. The Sixers officially listed Embiid as doubtful for those two games.
This game was postponed Nov. 30 by the NBA because of condensation on the court at the Wells Fargo Center.
TIMBERWOLVES 111, MAGIC 105, OT
MINNEAPOLIS (AP) - Andrew Wiggins scored 27 points and Ricky Rubio made a career-high six 3-pointers to lead Minnesota to the home win.
Karl-Anthony Towns had 23 points and 12 rebounds, Rubio added 22 points, eight rebounds and eight assists, and Wiggins forced overtime with a jumper with 10 seconds to play. The Wolves win for the eighth time in 11 games.
Elfrid Payton scored 21 points and Serge Ibaka had 17 points and 10 rebounds for the Magic, who came back from nine points down with five minutes to play to take the lead late in regulation.
GRIZZLIES 115, SUNS 96
PHOENIX (AP) - Mike Conley scored a career-high 38 points, Memphis just missed a franchise record with 16 3-pointers and the Grizzlies rolled past Phoenix.
Conley matched his career best with seven 3s (in 10 attempts) and made 12 of 18 shots overall in his fourth 30-point game of the season. He had five the rest of his career.
Marc Gasol and Zach Randolph each added 18 points for the Grizzlies in their third stop of a season-high, six-game road trip.
Devin Booker scored 22, running his string of 20-point games to 13, for Phoenix. Rookie Marquese Chriss added a career-high 20.
Phoenix never led and trailed by as many as 30 in matching its season worst with a fourth straight loss.