Tony Allen makes his 2009-10 season debut tonight against the Milwaukee Bucks after missing the first 20 games with a sore right ankle.

“I don’t know,” Doc Rivers said when asked what his expectations are for the defensive backcourt specialist. “Tony hasn’t played in so long. I’m looking for him not to do too much. Defensively is where we need help and need his help.”

Meanwhile, Rivers said Glen Davis is making progress in healing his right thumb, adding that Davis will ”probably be on the trip,” referring to the team’s West Coast trip at the end of the month.

Rivers did not speculate as to his availability and whether he would be activated.

After indicating that guard Tony Allen could be ready to face the Philadelphia 76ers, head coach Doc Rivers said on Wednesday that his defensive specialist still wasn’t quite ready to make his 2009 debut after injuring his left ankle in the preseason.

“I don’t have a clue when,” Rivers said. ‘No relapse. I really don’t Just not ready to play yet. It’s getting closer.”

Allen played in just one preseason game – on Oct. 9 against the Knicks – and hasn’t played in game action since.

WALTHAM  –  Tony Allen might finally be given the go-ahead to make his 2009-10 debut.

Celtics coach Doc Rivers said following Tuesday’s practice that Allen, a 27-year-old defensive specialist, might finally have enough confidence in his healed left ankle that he can play at full game speed.

“I think he’s very close, as close that he may play [Wednesday],” Rivers said. ”But I don’t know the answer yet. Wait till [Wednesday] and see how he feels.

“Tony looked good today,” Rivers said. “I think with him, it’s going to be a confidence thing. [Monday], I didn’t think he looked good. Today, I thought he looked terrific. He was exploding to the basket.”

The Celtics could use his athleticism off the bench to match that of the young 76ers, pressuring their backcourt of Lou Williams and Andre Iguodala. Tony Allen played in just one preseason game, playing eight minutes against the Knicks on Oct. 9. He missed both shots from the floor and was held scoreless.

WALTHAM  –  Doc Rivers knows his team hasn’t hit its stride yet.

He also realizes there’s 71 games left in the season.

But still, he, like everyone else, had to watch on Friday and Saturday as the Celtics dropped back-to-back games somewhat unexpectedly to the Hawks at home and the Pacers on the road.

The more alarming loss was Saturday when the weary Celts allowed Indiana to shoot 53 percent from the floor and score 113 points in a loss at Conseco Fieldhouse.

“It’s nothing big,” Rivers said following Tuesday’s practice. “We’ve done a lot of things average and we’re not an average team. When you play average on defense on certain things, and offense, you lose. It’s more of that. It’s nothing earth-shattering. It’s nothing we’re going to panic about. We know we have to get better.

“To me, the way we’ve played so far, we’ve been a spurt team. We’re not ready yet to be a 48-minute basketball team, that’s just not what we’ve done yet. We’re working on it.”

Meanwhile, one of the Celtics best defenders of the last two seasons — when healthy — has been Tony Allen. The guard has been out with a right ankle injury since off-season surgery but could be getting closer to returning as he is now practicing with the team.

“He did well actually,” Rivers said. “He moved and played great. He’s moving well. I’m not sure if he’s ready to play yet, honestly. I just don’t know yet because I do think he’s not sure of his injuries. There’s several times he’ll jump and you can see he’s clearly thinking about it and I don’t like putting players on the floor when they’re thinking about it because that leads to something else.”

WALTHAM —  Celtics coach Doc Rivers said Friday that despite some minor back issues with Glen Davis in the preseason, the power forward should be ready to go for Tuesday’s opener in Cleveland.

Davis played 16 minutes last Sunday in Toronto, scoring nine points off the bench.

However, the news is not as promising for Brian Scalabrine [right ankle] and Tony Allen [right knee].

“Scal, his ankle, I don’t expect him to be ready for opening night, but I’m not sure yet,” Rivers said. “Tony is a definite ‘no’ but everybody else is good.”

Celtics guard Tony Allen made an unexpected return to the court Friday night against the Knicks (recap here). Before the game, coach Doc Rivers said Allen, who underwent right ankle surgery in June, would not play until Sunday against the Nets.

Allen credits strength and conditioning coach Bryan Doo for his expedited comeback.

“He warmed me up pretty good, got to shoot a couple of jump shots, felt good on my landing,” Allen told WEEI.com after the game. “I just thought I’d give it a shot.”

Allen went scoreless (0-2 FG)  in eight minutes of play, contributing an assist and a steal while committing two turnovers and two fouls. He wasn’t playing for the box score, though. This was a test of his recovery.

“I felt good. I did some good things, I did some bad things. But most importantly, I just want to see how my ankle’s going to act tomorrow,” he said. “I got a little hands on deflections, my man couldn’t get past me, [but I] turned it over, being too aggressive, and didn’t let the game come to me are the bad things. But for the most part I was out there, I got up and down the court. Now I’ve got to see how it’s going to feel tomorrow when I wake up.”

For now, his anke bothers him. He soaked his foot in ice and noticeably favored it as he walked in the locker room after the game. But Allen is taking it one day at a time.

“It’s pretty sore right now but I can’t be [psychic Miss] Cleo in this situation to tell you how I’m going to be tomorrow,” he said. “So we’ll see what’s good. “

On Wednesday night, all eyes were on Kevin Garnett as he returned to the court for the first time in more than six months during the Celtics’ preseason opener against the Rockets in Hidalgo, Texas. Although Garnett’s playing time was limited, his knee injury looked out of mind when he drained the first shot of the game.

But Garnett was not the only player who returned to the Celtics looking to improve upon last season. Paul Pierce, Kendrick Perkins and Glen Davis lost weight, Rajon Rondo bulked up, and Ray Allen claims to be in the best shape of his career. See how the members of the 2008-09 team fared as they began the 2009-10 season.

Kevin Garnett
Last game: March 25 vs. Orlando Magic
17 minutes, 4 points (2-5 FG), 8 rebounds, 1 assist
Preseason opener: 13 minutes, 6 points (2-6 FG), 5 rebounds, 1 assist

Paul Pierce
Last game: May 17 vs. Orlando Magic
39 minutes, 16 points (4-13 FG), 7-10 FT, 2 rebounds, 3 assists
Preseason opener: 16 minutes, 8 points (2-6 FG), 4-4 FT, 1 rebound, 0 assist

Ray Allen
Last game: May 17 vs. Orlando Magic
41 minutes, 23 points (9-18 FG), 3-6 3PG, 4 rebounds, 3 assists
Preseason opener: 17 minutes, 8 points (3-6 FG), 0-2 3PG, 2 rebounds, 1 assist

Rajon Rondo
Last game: May 17 vs. Orlando Magic
37 minutes, 10 points (4-10 FG), 2-2 FT, 6 rebounds, 10 assists
Preseason opener: 17 minutes, 7 points (1-4 FG), 5-8 FT, 1 rebound, 3 assists

Kendrick Perkins
Last game: May 17 vs. Orlando Magic
39 minutes, 8 points (3-11 FG), 15 rebounds, 2 blocks
Preseason opener: 14 minutes, 3 points (1-2 FG), 3 rebounds, 2 blocks

Glen Davis
Last game: May 17 vs. Orlando Magic
31 minutes, 13 points (4-7 FG), 4 rebounds
Preseason opener: 23 minutes, 9 points (3-6 FG), 4 rebounds

Eddie House
Last game: May 17 vs. Orlando Magic
17 minutes, 2 points (1-3 FG), 0-1 3PG, 0 assists
Preseason opener: 21 minutes, 9 points (3-6 FG), 1-2 3PG, 0 assists

Brian Scalabrine
Last game: May 17 vs. Orlando Magic
13 minutes, 2 points (1-5 FG), 1 rebound, 2 assists
Preaseason opener: 18 minutes, 4 points (1-2 FG), 2 rebounds, 0 assists

J.R. Giddens
Last game: March 6 vs. Cleveland Cavaliers
1 minute, 0 points (0-0 FG), 1 rebound, 1 steal
Preseason opener: 13 minutes, 1 point (0-1 FG), 1 rebound, 0 steals

Tony Allen (ankle) did not play against the Rockets. Visit WEEI.com’s Green Street for live coverage from the TD Garden on Friday night as the Celtics take on the Knicks in their preseason home-opener.