MEMPHIS, Tenn. -- Toney Douglas is just three games into his tenure with his latest NBA team, but he looks as if he belongs in a Memphis Grizzlies uniform. He certainly possesses the franchise's grit-and-grind mentality.

The veteran reserve guard, signed by Memphis on Dec. 5, connected on two free throws with 0.5 seconds remaining to lift the Grizzlies to an 88-86 victory over the Portland Trail Blazers on Thursday night at FedExForum.

Douglas scored six points in the final 34 seconds as the Grizzlies rallied from a 13-point fourth-quarter deficit to win their fifth straight. In each of those games, the Grizzlies either led or trailed by three or fewer points in the final minute of regulation, or overtime, and won.

"Just a regular ol' day in Memphis," Grizzlies coach David Fizdale said. "We gave them everything we could. We just threw the kitchen sink at them. I don't know if we got lucky or what. I just know our guys competed really hard against them."

Center Marc Gasol led Memphis with a season-high 36 points, which included a 4-of-6 showing from beyond the arc, and JaMychal Green added a career-high 18 rebounds. Tony Allen contributed 15 points and 10 rebounds.

The Blazers were led by CJ McCollum with 24 points. Damian Lillard added 19 for Portland, which played without starting forward Maurice Harkless, who injured his left ankle Wednesday at Milwaukee.

Douglas finished with 11 points for the Grizzlies, but it was a combination of his tenacity and intensity in the closing minute that rescued Memphis, playing without injured point guard Mike Conley.

"He fits this group, honestly," Allen said. "He's a grit-and-grind character. He's feisty. He's tough. And as you can see he made big plays down the stretch."

Douglas was signed with an injury exception -- pursuant to the NBA's hardship rules -- and has felt comfortable from the outset, even if his locker is the only one without a nameplate. Douglas, who is with his seventh NBA team, played the entire fourth quarter.

"I feel like I've been here the whole year," Douglas said. "I'm comfortable with Coach Fiz. I played with him in Miami. I know what he expects.

"I'm here to bring veteran leadership to the younger guys, let them know what they have to do to get better."

Memphis trailed 77-64 with 7:14 left but put together an 18-4 run that ended on back-to-back 3-pointers by Gasol and Troy Daniels. Daniels connected from 30 feet to give the Grizzlies an 82-81 lead with 1:35 to go.

The lead changed hands four times in the final 1:26. Douglas went 4 of 4 from the free throw line in the final 19.2 seconds.

"If a game's close, teams (that play Memphis) know they are in a dogfight," Douglas said. "We showed great composure."

With no timeouts remaining, Douglas drove downcourt after Portland's Mason Plumlee tied the game at 86 with seven seconds left on a free throw. Douglas was fouled by Lillard with 0.5 seconds remaining.

"It's a tough (foul) call," Lillard said. "I think at that point in the game there are some calls that you make and there are some you just play basketball."

Memphis overcame 35.6 percent field-goal shooting. Portland shot 30.5 percent.

"Well, it was a tough loss," Blazers coach Terry Stotts said. "Our offense all game struggled. We struggled to make shots, we didn't finish around the rim, and we didn't make shots on the perimeter.

"You certainly give Memphis credit for playing hard. That's how they've won the last two games. They find ways to win games in the last minutes of games."

Portland led 50-43 at halftime, then built a double-digit lead before watching the Grizzlies battle back. Memphis trailed 60-48 after McCollum drilled a 3-pointer early in the third quarter, but the Grizzlies recovered behind Gasol and Daniels. Daniels' jumper from the left wing followed a three-point play from Gasol and trimmed the Portland lead to 62-59 with 3:26 to go in the third.

The Trail Blazers led 69-61 entering the final quarter.

NOTES: On an injury-riddled Memphis team, C Marc Gasol is the only starter averaging double figures. Gasol is averaging 19.2 points. JaMychal Green is next at 9.5. ... Blazers F Al-Farouq Aminu hit just 2 of 9 shots and scored five points. In three games back from a left calf strain, he is 4 of 17 from the floor. ... The Grizzlies were 9-21 when G Mike Conley was out with an injury during the 2015-16 season. They are 5-1 without him this season. Conley is out for at least another month with a fracture in his back. ... The Blazers entered the game with the worst defensive rating in the league. Portland was allowing 109.9 points per 100 possessions. ... Before the game, the Grizzlies announced general manager Chris Wallace, executive vice president of basketball operations John Hollinger and executive vice president of player personnel Ed Stefanski were signed to multiyear extensions. Each was in the final year of his contract. Terms were not disclosed.