Smith connected on a 23-foot jumper from the right wing as the 24-second clock expired to put New York up 117-113 with 1:30 to play, then swished a 3-pointer from beyond the 3-point line with 56.8 seconds left that all but sealed New York's 50th win of the season.
It's the first time the Knicks have reached the landmark in 13 years.
Russell Westbrook had 37 points, 11 rebounds and eight assists for Oklahoma City, which fell a game behind San Antonio for first place in the West with five games left.
Kevin Durant scored 27, falling behind Anthony in the NBA scoring race.
CLIPPERS 109, LAKERS 95
LOS ANGELES (AP) — Blake Griffin had 24 points and 12 rebounds, and the playoff-bound Clippers beat the Lakers to clinch their first Pacific Division title in franchise history against a team that has long overshadowed them.
Chris Paul added 24 points and 12 assists in helping the Clippers sweep the Lakers 4-0 for the first time since Donald Sterling bought the team in 1981. The 1974-75 team, known as the Buffalo Braves, had the franchise's only other sweep of the Lakers.
Fans chanted, "Sweep! Sweep!" in the closing seconds.
Jamal Crawford had 20 points off the bench, DeAndre Jordan had 13 rebounds and Caron Butler scored 14 points.
Dwight Howard scored 25 points, including 9 of 13 free throws, for the Lakers, who played without injured starters Steve Nash and Metta World Peace. Kobe Bryant added 25 points, 10 assists and seven rebounds, and Pau Gasol had 12 points and 13 rebounds as the Lakers' three-game winning streak ended.
JAZZ 97, WARRIORS 90
OAKLAND, Calif. (AP) — Mo Williams scored 25 points, Al Jefferson added 19 points and 12 rebounds, and Utah regained the Western Conference's final playoff position by holding off Golden State.
Williams made a 3-pointer with 13.4 seconds remaining to put Utah ahead by six and spoil Golden State's shot to clinch a playoff berth in front of a sellout crowd of 19,596. The Jazz moved a half-game ahead of the Los Angeles Lakers for the eighth seed.
Stephen Curry scored 17 of his 22 points in the first half and Klay Thompson had 20 points for the Warriors, who were trying to clinch a post-season spot for the first time since 2007 and just the second in 19 years.
CELTICS 107, WIZARDS 96
BOSTON (AP) — Brandon Bass scored 20 points and Boston Celtics, helped by the return of Kevin Garnett and Paul Pierce, beat Washington.
Bass missed his season high by just two points and led the Celtics with eight points in the third quarter, when they hit 75 per cent of their shots, outscored Washington 31-19 and stretched a 56-52 halftime lead to 87-71.
They led by at least 10 points the rest of the way to get just their fourth win in 12 games.
Garnett had 12 points and six rebounds in 24 minutes after missing eight games with an inflamed left ankle. Pierce finished with 15 points in 30 minutes after missing Friday night's 97-91 loss to the Cleveland Cavaliers with a sore left ankle.
PISTONS 99, BULLS 85
AUBURN HILLS, Mich. (AP) — Brandon Knight scored 20 points to help Detroit snap an 18-game losing streak against Chicago.
Jonas Jerebko added 17 points and a season-high nine rebounds for the Pistons, who ended an eight-game home skid.
The Bulls led by as many as 11 points in the first quarter but Detroit gradually caught up and took the lead in the second after starting the period on a 12-4 run.
Carlos Boozer had 21 points and 10 rebounds for the post-season-bound Bulls, who are fighting to secure the fourth seed in the Eastern Conference.
GRIZZLIES 89, KINGS 87
SACRAMENTO, Calif. (AP) — Mike Conley scored 25 points, making the go-ahead basket with 30 seconds left and leading Memphis over struggling Sacramento.
Memphis made some big plays in the game's final minute to get the victory, its fifth in six games. The win gave the Grizzlies a four-game sweep of the Kings for the first time in franchise history.
Quincey Pondexter scored 17 points and Marc Gasol had 15 points, 10 rebounds and five blocks for the Grizzlies. Tony Allen scored 12 points.
DeMarcus Cousins had 22 points and nine rebounds for the Kings, who have dropped four straight. Isaiah Thomas had 18 points, eight assists and six rebounds. Toney Douglas scored 14 points and Jimmer Fredette added 13.
MAVERICKS 96, TRAIL BLAZERS 91
PORTLAND, Ore. (AP) — Chris Kaman scored a season-high 26 points and Dallas boosted its faint playoff hopes by beating slumping Portland.
Kaman added 11 rebounds for the Mavericks, who were 2 1/2 games back of Utah for the eighth and final spot in the Western Conference, and two games behind the Lakers. Dallas (38-39) has just five games left, but four of those are at home.
The Mavs led by as many as 26 points, but the Blazers closed the gap in the fourth quarter — even after sitting most of their starters.
Will Barton came off the bench with 22 points and 13 rebounds for the Blazers, who have lost eight straight for their longest losing streak since the 2005-06 season.
HORNETS 95, SUNS 92
PHOENIX (AP) — Anthony Davis scored 20 points, Eric Gordon and Ryan Anderson added 17 apiece and New Orleans handed Phoenix its franchise-record seventh consecutive home loss.
Luis Scola scored 17 for the Suns, losers of a season-worst nine straight overall and 15 of their last 17. Markieff Morris and Jared Dudley scored 15 apiece for Phoenix.
The Suns, down by 16 with nine minutes to play, cut it to 85-82 on Goran Dragic's two free throws with 3:03 left. But Anderson's rebound basket and two free throws by Davis boosted it to 89-82 and the Hornets held on from there.
New Orleans snapped an eight-game road losing streak.
CAVALIERS 91, MAGIC 85
CLEVELAND (AP) — Alonzo Gee scored 19 points and Cleveland rallied in the fourth quarter to beat Orlando.
Tristan Thompson had 15 points and 16 rebounds for the Cavaliers, who have won two in a row for the first time since Feb. 26-27.
Cleveland, which broke a season-high, 10-game losing streak Friday in Boston, trailed by seven points late in the third quarter, but took the lead for good early in the fourth and made clutch plays down the stretch.
Tobias Harris scored 26 points while Nikola Vucevic added 21 points and 21 rebounds for Orlando, which has lost five in a row and 13 of 14. The Magic have dropped 11 straight away from home — the second-longest road losing streak in franchise history.