O.J. Mayo scored 26 points and Rudy Gay added 20 to lead the Grizzlies to a 98-90 victory over mostly Atlanta's reserves.
"I wanted to win because you're only as good as your last game," Mayo said with a laugh. "I really wanted to get a win to give [something] to our fans."
Marc Gasol finished with 19 points for Memphis, which snapped a two-game losing streak. Hakim Warrick added 15 points, and Mike Conley finished with 12 points and seven assists.
Flip Murray led the Hawks with 29 points, including 20 in the second half to keep Atlanta close. Maurice Evans chipped in 21 points.
The Hawks, who were solidly in the Eastern Conference's fourth playoff spot, didn't bother using their regulars against the Grizzlies (24-58).
Starters Joe Johnson, Mike Bibby, Al Horford and Marvin Williams sat out for the Hawks. Josh Smith played only 10 minutes in the first quarter.
"We got a chance to evaluate some of these young guys and get some of the other guys some rest going into the [playoffs]," Hawks coach Mike Woodson said.
With their usual starters in street clothes, the Hawks started Mario West for the third time this season, and Murray got his second start.
Memphis coach Lionel Hollins had to guard against his team having a lapse.
"It's hard just to keep my group focused," said Hollins, who had a 13-26 record after taking over the team when Marc Iavaroni was fired in January. "It's a tough situation, but it is the game. You've got to just do what you do, and not worry about it. Just go out and play. It's not that big of a deal."
Despite the absence of the Atlanta regulars, the Hawks started fast, building an early 10-point lead and staying even with Memphis for awhile as the Grizzlies used their normal rotation.
But the Hawks reserves weren't up to the defensive task, and Memphis was getting to the basket for dunks, scoring 32 points in the paint during the first half, and carrying a 53-43 lead into the break.
"[The Grizzlies] were hitting some tough shots," Murray said. "We had some turnovers in the first half that allowed them to get out on the break and get some easy baskets."
Mayo had 17 points for Memphis, connecting on seven of his 10 shots in the half. The Grizzlies shot 62 percent in the first two quarters.
Memphis extended the lead to 14 -- its biggest of the game -- in the early part of the third, but Murray led an Atlanta comeback.
Murray had 18 in the quarter. His layup gave Atlanta its first lead of the second half at 63-62, and his two free throws later tied the game at 65.
Mayo scored seven points in the final minute of the third to help Memphis carry a 72-69 lead into the fourth.
Atlanta would lead again in the fourth, 75-72, but the Grizzlies used a pair of 7-0 runs in the middle of the stanza, eventually building their advantage to 11 in the quarter.
"I didn't think we were sharp from a defensive standpoint, especially coming down the stretch run," Woodson said. "A lot of these young guys hadn't played a lot of minutes. I thought fatigue set in and defensively we couldn't get stops when we needed them."
With that, the Hawks prepared for the postseason, while Memphis went into the offseason, focusing on strides made in the last half of the year and hoping to build on that for next season, including adding more interest to its fan base.
"At least, their last memory is that we got a win here, and look forward to something next year," Mayo said.
Before the game, the Grizzlies honored Gene Bartow, president of Hoops LP, which operates the Memphis Grizzlies and FedExForum, for his recent induction into the National Collegiate Basketball Hall of Fame. Bartow was not present for the ceremony. Earlier in the day, it was announced that Bartow, who coached at UCLA, Memphis State (now the University of Memphis) and started the basketball program at UAB, has stomach cancer. ... The Hawks face the Miami Heat in the first round of the Eastern Conference playoffs. Mayo set a franchise record for points by a rookie with 1,516, surpassing Shareef Abdur-Rahim?s 1,494 in the 1996-97 season. Grizzlies C Marc Gasol was 7-for-12 from the field, setting a franchise rookie record for field goal percentage in a season with 53 percent. The previous record was held by his brother, Pau, with 51.8 percent in 2001-02.