Leonard's basket came after Dion Waiters' jumper with 9.5 seconds to go put Cleveland up 95-93.
Kyrie Irving, who was held to a season-low six points, missed a desperation runner from the top of the key as time expired.
Tony Parker led the Spurs with 24 points while Gary Neal scored 15.
Duncan, who had missed eight of the last nine games with a sore left knee, scored 13 points in 25 minutes. Ginobili had five points in nine minutes off the bench after missing nine of the last 13 games with a tight left hamstring.
RAPTORS 92, KNICKS 88
NEW YORK -- Reserve Alan Anderson scored 26 points in one of the few good offensive performances for either team, and Toronto beat New York for its fourth straight victory.
DeMar DeRozan added 20 points for the Raptors, who overcame a 4-for-21 performance from Rudy Gay because Knicks star Carmelo Anthony was just as bad. Anthony finished with 12 points and 12 rebounds but shot 5 of 24 for the Knicks, who dropped their final two games leading into the All-Star break.
Gay finished with 11 points one night after hitting the go-ahead basket with 4.9 seconds left in a victory over Denver.
MAVERICKS 123, KINGS 100
Carter scored 17 of Dallas' last 21 points in the third quarter to help turn aside a Sacramento rally. He made five of seven 3-pointers in the quarter and ended the night with 21,796 career points for 29th on the all-time list. Bird had 21,791.
Dirk Nowitzki finished with 17 points, including a 3-pointer to put Dallas ahead 100-79 early in the fourth quarter.
Tyreke Evans scored 23 as the Kings lost their 18th regular season game in a row in Dallas.
NETS 119, NUGGETS 108
NEW YORK -- Joe Johnson scored 26 points, including five 3-pointers, and C.J Watson added 25 points and five 3s to help Brooklyn beat Denver.
The 119 points were a season high for the Nets, who also tied a season best with 16 3-pointers.
Brooklyn is now 2-1 in games played without star point guard Deron Williams, who has sat out the last two due to sore ankles.
Ty Lawson led the Nuggets with 26 points and hit all of his five 3-point attempts.
PACERS 101, BOBCATS 77
INDIANAPOLIS -- Paul George posted his first career triple-double with 23 points, 12 rebounds and a career-high 12 assists, and Indiana snapped a two-game skid with a win over Charlotte.
The first quarter started as a shootout with Indiana and Charlotte combining for 59 points on 55.6 percent shooting. The Pacers held a 30-29 lead after the first before limiting the Bobcats to 23 percent shooting (14-for-61) over the final three quarters.
HAWKS 108, MAGIC 76
The Hawks led by as many as 38 and decimated the Magic defense on the way to earning their ninth consecutive regular-season win over their division rivals.
The Magic, who have lost 24 of their last 27 games, were dealt a blow earlier in the day when the NBA announced that forward Hedo Turkoglu will be suspended 20 games for a positive steroid test.
CELTICS 71, BULLS 69
BOSTON -- Kevin Garnett scored eight of his 12 points in the fourth quarter and added 11 rebounds, and Boston overcame poor shooting to beat Chicago.
Paul Pierce went only 2 for 12 from the floor but he hit a 3-pointer that bounced around the rim to give Boston a five-point lead with 3 minutes to play. The Celtics shot just 36.8 percent but still had the advantage over the Bulls, who made just 36.5 percent of their shots.
The Celtics' eight points in the third quarter were the team's fewest in a period this season.
PISTONS 96, WIZARDS 85
AUBURN HILLS, Mich. -- Will Bynum scored six of his 20 points during a late run to help lead Detroit to a win over Washington.
With the game tied at 76, Bynum scored six straight points to give Detroit the lead with 3:23 to play. Jose Calderon pushed it to nine with a 3-pointer, and the margin was 11 before John Wall broke Detroit's surge.
Calderon led the Pistons with 24 points, while Greg Monroe finished with 16 points and 18 rebounds as Detroit rebounded from a lopsided home loss Monday to New Orleans
Emeka Okafor had 20 points for the Wizards, and Wall finished with 16 points and nine assists.
BUCKS 94, 76ERS 92
Samuel Dalembert had 17 points and 14 rebounds for the Bucks, who ended a four-game losing streak. Milwaukee heads into the All-Star break with a four-game lead over the 76ers for the eighth and final playoff spot in the Eastern Conference.
Milwaukee didn't take its first lead until about 9:20 remained.
JAZZ 97, TIMBERWOLVES 93
Jefferson helped the Jazz overcome a sluggish start against his former team to pick up a rare road win against a Western Conference opponent. Utah is 4-13 on the road against the West.
HORNETS 99, TRAIL BLAZERS 63
NEW ORLEANS -- Anthony Davis had 21 points and 11 rebounds, and New Orleans handed Portland its fifth straight loss.
Davis, who missed all seven of his field goal attempts on Monday night in Detroit, was 10 of 17 against Portland, scoring on an array of dunks, tip-shots and even jumpers from as deep as 20 feet. Ryan Anderson added 14 points and Jason Smith 13, both in reserve roles. Greivis Vasquez had 10 points and eight assists in 26 minutes.
Copyright 2013 by The Associated Press
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