With their star sitting in the locker room after an early ejection, the Warriors needed someone else to carry the load.
"We wanted to step it up and pick up the slack for Baron," Stephen Jackson said. "Because on nights when we don't have it, he does it for us."
Richardson's fourth-quarter spurt helped avoid a loss to the NBA's worst team that would have dealt a crushing blow to the Warriors' playoff hopes.
Golden State, which hasn't made the postseason since 1994, entered the day two games out of a playoff spot. Denver and the Los Angeles Clippers were tied for seventh place in the Western Conference heading into the Nuggets' game at Seattle later Sunday.
"About the time you hope we'll finally have an easy game you have one of these," coach Don Nelson said. "I'm very happy we found a way to win this one because we couldn't afford to lose this one and stay in the hunt."
When the Warriors fell behind by eight points early in the fourth quarter, their chances appeared slim. Richardson then took over by scoring the next eight points of the game and 11 during a 17-4 run that put Golden State up 108-103 with just over 4 minutes left.
Richardson scored on a drive to start the run and then converted an acrobatic three-point play. He took a pass from Mickael Pietrus near the basket and made a twisting shot with his back to the basket while drawing a foul from Pau Gasol.
Richardson made the free throw and then hit a 3-pointer to tie the game the next trip down. Richardson added another 3-pointer during the run and Pietrus hit two as well for Golden State.
Jackson's three-point play with 1:14 to play gave the Warriors a 117-109 lead and they held on from there.
"When somebody screws up, the other guys pick it up," Nelson said. "That's why they call it a team sport. We've all screwed up. Baron's pretty happy that he won't be wearing the goat cap."
Golden State finished with a season-high 39 assists, getting nine from Ellis and Jackson, and eight from Richardson.
"Everybody had to be playmakers without having Baron out there," Jackson said. "We all just stayed aggressive and shared the ball and that's how we were able to get a run going in the fourth quarter."
"They made plays when they needed to offensively and defensively and they came up with some stops," Gasol said. "They were very aggressive down the stretch and played with a lot of confidence making a lot of tough shots. They definitely made a lot of 3s when they most needed to when we had that lead."
Davis, who leads the Warriors in scoring and assists, was called for a pair of technical fouls with 1:22 remaining in the first quarter, leading to his ejection.
After scoring on a breakaway layup, Davis was called for the first technical by Tony Brown on the defensive end. Davis then slammed his hand on the scorer's table -- sending a piece of candy flying out of a jar -- as he walked to the bench during a timeout and was immediately called for the second technical by referee Steve Javie.
The Warriors have struggled this season without Davis, who missed 13 games earlier this season after undergoing arthroscopic surgery on his left knee in February.
Golden State went 4-9 during his absence, but has made a playoff push since his return, winning eight of 12 games before Sunday.
"In the past, we've played awful without him," Harrington said. "I think that showed growth for us that without him we were able to step it up."
Grizzlies F Mike Miller, who scored 78 points in the first two meetings against Golden State, missed the game with patellar tendinitis in both knees. ... Nelson also got called for a technical foul late in the second quarter. ... Golden State's Matt Barnes was called for a flagrant foul late in the third quarter for a hard foul on Junior Harrington's drive.