Pierce, who is recovering from a left midfoot sprain, was in the lineup against the New Orleans Hornets on Wednesday and plans to participate in All-Star Weekend starting Friday in Dallas.
"It's getting better, it's still a little sore," Pierce told The Boston Globe before the game. "I'm hoping over the break, with some time off, I can continue the process of getting better. Definitely, the weekend is going to help. I plan on playing tonight and plan on being in the All-Star Game, plan on being in everything."
Pierce played 34 minutes and had 15 points, but the Celtics again struggled in the second half in a 93-85 loss.
Allen was scratched from the lineup against the Hornets.
The team said Allen, who averages 16 points a game, has been bothered by back spams.
Pierce is scheduled to participate in the 3-point Shootout on Saturday and told the Globe he's been practicing for the event. He also suggested he'd like to play 10-12 minutes during the actual All-Star Game on Sunday.
The Hornets, meanwhile, got rookie shooting guard Marcus Thornton back from a lower back bruise that has sidelined him for three games.
Hornets coach Jeff Bower said Morris Peterson will remain the starter at shooting guard, with Thornton coming off the bench. Thornton was the starter before his injury and has been averaging 10.9 points.
Thornton scored just two points in nine minutes, while Peterson had 16 and 10 rebounds.
Information from the Associated Press was used in this report