With Pierce nursing a bruised right heel, Boston started 0-3 for the first time in five seasons but has bounced back with four consecutive wins since the forward's return.
After scoring a combined 21 points in his first two games, Pierce has topped 20 in each of his past two and had a season-high 24 in an 89-70 victory over New Jersey on Wednesday.
"He's fitting right in and getting his rhythm," point guard Rajon Rondo said.
Pierce's effort helped the Celtics overcome the loss to Allen, who fought through a cold to score a team-best 27 points during a 100-92 win over Washington on Monday.
Allen was told to stay away from Thursday's practice, but coach Doc Rivers said that the guard was "feeling a lot better." Rivers, though, added that Allen remains questionable for Friday's game.
"I think he'll play, but I have no idea," Rivers said.
If he returns, Allen will try to help Boston earn its eight straight home win over Indiana (4-2) and 12th in 15 overall matchups. The Pacers, however, pulled out a 107-100 victory over the Celtics on March 28 - last season's final meeting - as Roy Hibbert scored 26 points against a depleted Boston frontcourt.
Indiana could use another such performance as it tries to split its season-high, four-game road trip. Hibbert had a team-best 16 points and 12 rebounds during the latest stop on that trek Wednesday, but the Pacers brought little else in a 118-83 drubbing to Miami.
Leading scorer Danny Granger had a season-low six points during another poor shooting performance. Granger, who is connecting at just a 31.7 percent rate, this season missed 11 of 13 attempts against the Heat, including 6 of 7 from 3-point range.
"It's one loss. I believe in this team. I think we have a chance to win every night in every building against any team," coach Frank Vogel said. "The game was a lack of execution, we missed open shots, and their (effectiveness on) defense. The combination was a perfect storm."
Granger has made 35.9 percent of his shots in his last nine games against Boston but has averaged 19.1 points. He made six of his 12 shots during the win in March while scoring 18 points.
The Pacers will also have David West, who scored 32 points for New Orleans during an 89-85 loss to Boston on March 19. West, though, has averaged 11.8 points this season, far fewer than his 19.2 per game over the previous six campaigns.
Pierce has scored at least 20 points in five of his last six matchups with the Pacers and had a team-best 23 during the loss in Indiana in March. He's also scored 20 or more points during three of the Celtics' past four home wins over the Pacers.
Allen, meanwhile, hasn't been as effective over the past three meetings at the TD Garden, averaging 14.0 points, and Kevin Garnett has a combined 45 points over his last five overall matchups with Indiana.
If he doesn't have any more problems with his right hamstring, the Celtics' Jermaine O'Neal will face his former team for the second time since Jan. 19, 2010. He has missed four of his teams' games against the Pacers.