Nate Robinson had a season-high 27 points, Wilson Chandler added 23, and David Lee had 22 points and 12 rebounds to help the Knicks snap a three-game losing streak.
Antawn Jamison had 29 points and 13 rebounds for the Wizards, who dropped their fifth straight and fell to 1-10, their worst since the 1966 Baltimore Bullets also opened 1-10. Caron Butler finished with 23 points, 19 in the second half.
The Knicks used seven players for the second consecutive night, following a loss in Milwaukee. The Knicks are short-handed after making a pair of trades Friday, and the three players they got back, Al Harrington, Cuttino Mobley and Tim Thomas, aren't eligible to play until completing physicals.
Stephon Marbury didn't dress, a night after coach Mike D'Antoni said the point guard declined a chance to play for the first time this season. The Knicks instead had Jerome James, who hasn't played this season, in uniform to reach the league-mandated eight active players, and got only three field goals from their bench.
Jamison hit a jumper and 3-pointer early in the fourth to give Washington a 94-93 lead, its first lead since it was 10-7 in the opening minutes. It went back-and-forth from there until Richardson hit a pair of free throws with 2:32 left, then scored on a drive to make it 120-113 with 1:03 to play.
Richardson tied John Starks' record for 3-pointers in a quarter by hitting six in the first period, helping New York build a 35-29 lead. The Knicks shot only 7-of-26 (27 percent) in the second and Washington trimmed the lead to 60-58.
The Knicks seemed poised to seize control when they scored seven straight points to open an 83-69 lead on Lee's free throws with 6:27 left in the third. But New York had only three field goals after that, and the Wizards were within 91-89 after Butler's 3-pointer with 3.6 seconds remaining.
