Davis had 27 points and 10 rebounds, Roberts scored 17 of his 19 points in the second half, and New Orleans beat the Atlanta Hawks 105-100 on Wednesday night.
"I'm always telling our guys, `Everybody has written you guys off, so what do you have to lose? Just go out there and play. I've got your back either way," Pelicans coach Monty Williams said.
"Roberts made some big shots," said Hawks guard Jeff Teague, who had 11 points and 13 assists. "We just got stagnant on defense. Our intensity on defense just wasn't there. We didn't play with attention to detail in the last couple of plays."
Davis and Roberts made Atlanta pay, each scoring six points in the final 3:40.
Davis has been stellar all season, and his performance against Atlanta marked the 16th time he's had at least 20 points and 10 rebounds in the same game.
Roberts only recently moved into a starting role at point guard because of Jrue Holiday's stress fracture in his right shin.
Roberts made only one of five shots in the first half before turning in one of the best second halves of his young career.
"He's growing up and he understands when to make plays," Davis said.
Roberts did have one glaring error when he had a turnover that led to a score during a late 7-0 Atlanta run that trimmed the Hawks' 10-point deficit to three with a little less than a minute left. Roberts made up for it with a running, off-balance floater on New Orleans' next possession to make it 100-95 with 20 seconds to go.
"That was a tough turnover right there," Roberts said. "I just try to move on and focus on the next play. ... I was going to get it back and I was able to make that floater and finish them off."
Atlanta was in position to win when Mike Scott's 3-pointer capped an 8-0 run and gave the Hawks an 83-76 lead with 7:45 to play, but the Pelicans then ran off nine straight points to regain the lead.
"That's a tough loss for our group," Hawks coach Mike Budenholzer said, referring to his club's blown fourth-quarter lead. "Our execution needs to improve when we're in that situation."
The Hawks led for the entire third quarter, taking their largest lead at 54-47 on Carroll's 3 12 seconds into the period.
Scott hit four 3-pointers and finished with 16 points for the Hawks, while Lou Williams had 11 points.
The teams stayed within single digits of each other for nearly the entire game. The largest lead for either team was 10 for New Orleans after Davis' free throws late in the fourth quarter. That lead lasted all of 8 seconds before Scott hit a 3.
Atlanta had 14 3s on 30 attempts from deep, with Carroll hitting four. The Hawks had one stretch in which they hit nine straight 3-point attempts -- their last four of the second quarter and first five of the third.
The Pelicans, however, scored 20 points on free throws, while Atlanta had only 10. New Orleans also outrebounded Atlanta 50-38.
The Pelicans have scheduled a ceremony on Thursday to rename the New Orleans Arena as the Smoothie King Center. Pelicans officials confirmed to The Associated Press and several other media outlets on Wednesday afternoon that they had reached a 10-year naming rights agreement with the Louisiana-based company. ... Davis blocked one shot, ending a streak of seven games in which he'd blocked at least four. ... Atlanta's Kyle Korver was 2 for 5 from 3-point range.