UPDATE: Garnett participated in Celtics’ morning shootaround and his status for Wednesday night’s game against the Detroit Pistons has been upgraded to probable.

Boston Celtics power forward Kevin Garnett is doubtful for Wednesday’s home contest with the Detroit Pistons with a right hip flexor suffered against the Chicago Bulls on Sunday. He sat out practice on Tuesday, but coach Doc Rivers said the injury isn’t serious.

“Kevin has a 50/50 chance (of playing Wednesday),” Rivers said. “We’ll find out (Wednesday). It’s nothing bad with Kevin. But (Celtics trainer Ed Lacerte) really suggested two days off and then he said today, ‘Maybe three days off.’ So we’ll find that out (Wednesday).”

Keep in mind “The Green Team” travels to the Windy City to take on the Bulls on Thursday — so Doc could be saving K.G. for the rematch with Chicago.

In his last five games, Garnett is averaging 17.6 points per game on 53.7% shooting — accompanied by 9.6 rebounds, 2.2 assists, and 1.2 blocks.

The Celtics are already without a key frontcourt contributor — Brandon Bass — who’s out with a right knee injury for the next two weeks.

Small forward Mickael Pietrus is also doubtful after missing part of Tuesday’s practice to get treatment on the right knee that was operated on this offseason.

Center Jermaine O’Neal could be returning to the lineup. He’s missed the last two games with a left shoulder injury, but he participated in practice Tuesday.

Frontline Replacements: Should Garnett be sidelined, it’s looking like the Celtics will be counting on rookie first-round pick JaJuan Johnson and Chris Wilcox to play significant minutes.

Forward Brandon Bass, the Boston Celtics’ stellar sixth man, will miss 10-to-14 days with inflammation in his right knee, and if you bet on basketball, you can bet it could have been a key setback before Sunday’s 95-91 win against the Chicago Bulls.

Rivers said the news came as a bit of a surprise to him, as he was informed by team trainer Eddie Lacerte on Sunday morning that Bass almost certainly will be out through the All-Star break — which begins February 23rd, a game that sees many do betting online between the East and West in Orlando, the home of the Magic.

The replacement for Bass, rookie JaJuan Johnson, played a season-high 33 minutes and scored 12 points against Chicago.  Johnson added four rebounds (three offensive), two steals, one assist and one block.

More injuries: Jermaine O’Neal (shoulder/knee) also missed the win over the Bulls, and Chris Wilcox stepped up in the starting lineup and registered 11 (5-6 FG) and nine rebounds in 26 minutes of action.

Last night was a very special night at the TD Garden, as Captain Paul Pierce passed Celtics Legend Larry Bird on the Boston Celtics all-time scoring list. Heading into the game Pierce was just ten points shy of passing Larry Bird, who held the second place spot on the list with 21,791 total points. Fittingly, Pierce hit a three pointer to beat the record early in the 3rd quarter.

Fans in attendance, including Pierce’s mother and wife, gave The Truth a well-deserved standing ovation. Pierce is now 2nd among the franchise’s all-time leading scorers with 21,797 points, behind Celtics Legend John Havlicek (26,395).

Game Notes: Rajon Rondo collected 14 assists for the second straight contest, Kevin Garnett led the team in scoring with 22 points on 10-15 shooting, and Paul Pierce tallied 15 points, 8 rebounds and 9 assists. Ray Allen added 17, while Brandon Bass provided 13 off the bench.

Stat: Celtics are the NBA’s first-ranked defense, allowing 86.5 points per game.

Next: 14-10 Boston Celtics vs. 14-11 Los Angeles Lakers, Thursday in the Garden at 8 ET.

Boston Celtics forward Paul Pierce has been named the Eastern Conference Player of the Week, respectively, for the week ending February 5.

Pierce averaged 22.0 points, 6.3 assists and 5.8 rebounds to help the Celtics get to 4-0 last week. He had 30 points, seven rebounds and five assists in a 91-89 win over New York on Friday.

On Sunday, Pierce registered 21 points along with six rebounds and six assists in the Celtics’ 98-80 win over Memphis — their eighth win in the last nine games — improving to 13-10 this season.

Garnett had 12 points, 10 rebounds, four assists, four blocks and three steals in last night’s comeback victory over Orlando.

Boston Celtics point guard Rajon Rondo will once again sit out Thursday night in Orlando as he continues to nurse a wrist injury, according to the Boston Globe’s Gary Washburn.

Rondo originally suffered the injury during a hard spill against the Toronto Raptors last Wednesday night, and has missed the Celtics’ three games since.

Rondo is also listed as doubtful for Friday against Phoenix.

Also, Ray Allen will likely miss tonight’s game contest against the Magic with a jammed left ankle.

Russell Westbrook hit a 3-pointer and then shimmied his hands down his torso, bent his body at the knees and strutted down the sideline in celebration.

Just 39 seconds later — this time with less than a minute left in the game — he did it all over again.

Westbrook scored 26 points, including two of Oklahoma City’s four 3-pointers in the final 2 minutes, to help the Thunder beat the slumping Celtics 97-88 on Monday night. Kevin Durant scored 28 with seven rebounds for Oklahoma City, which won its seventh consecutive game.

“They started doubling K.D. later in the game,” Westbrook said. “I just tried to be aggressive and find my open spots.”

Paul Pierce scored 24 points, Kevin Garnett had 12 points and 12 rebounds and Jermaine O’Neal had 12 points and 11 boards for the Celtics. Rajon Rondo scored 12 points with nine rebounds and nine assists for Boston, which lost a fifth straight game for the first time in the New Big 3 era.

“None of us likes to lose; that’s the frustrating part,” Pierce said. “I think I like where we are headed, there are just little things that are really killing us.”

After trailing by 10 points to start the fourth quarter, the Celtics cut the deficit to two before Durant hit a 3 that made it 81-76 with 4:42 left. Garnett made a pair of free throws, then Durant threw down a tomahawk dunk.

Oklahoma City then hit four 3-pointers in a row — one from Thabo Sefolosha, two from Westbrook and another from Sefolosha that made it 95-85 with 24 seconds left. The Thunder were 2 for 11 from 3-point range in the first three quarters and 5 for 8 in the fourth.

“We stayed with it,” Durant said. “We made some good shots. Our offense is predicated on the drive-and-kick; that’s what we work on every day.”

Kendrick Perkins had seven points and five rebounds in his first game back in Boston since the trade that sent him to Oklahoma City and broke up the starting lineup from the Celtics’ 2008 NBA championship team. In the first quarter, his old team played a video on the scoreboard with highlights from his 7½ years in Boston.

“Mentally, I was out of it,” said Perkins, the 27th pick in the 2003 draft. “It was unbelievable. I really appreciated it. It was something they didn’t have to do.”

Perkins went over to the Celtics bench before the opening tip to hug the coaches and chest-bump some of his former teammates, and midway through the first quarter a video tribute was played on the scoreboard. The crowd gave him a standing ovation, which Perkins acknowledged by walking to center court alone and waving.

“It was emotional for him. He grew up here,” Thunder coach Scott Brooks said. “He’s loved by his former coach, teammates and the fans, and rightfully so. He does everything that you want your player to do. … That’s a classy organization, for what they did on the scoreboard.”

Boston cut the deficit to 83-80 with 2:25 to play, but Westbrook cut across the lane and whipped a two-handed pass to Sefolosha in the corner for the 3. After Rondo scored on a putback, Westbrook hit a 3-pointer of his own — then celebrated by strutting down the sideline.

Garnett hit Mickael Pietrus to set up a Celtics 3-pointer, but Westbrook answered again to make it 92-85.

The Celtics had not had a five-game losing streak since they lost seven straight and eight of the last nine games of the 2006-07 season, a year when they also had an 18-game losing streak that was the longest in franchise history. That summer they began assembling the New Big 3 — bringing in Garnett and Ray Allen to join Pierce, with Rondo and Perkins rounding out the lineup for a team that won the franchise’s 17th NBA title.

Boston returned to the finals in 2010, but Perkins tore up his knee in Game 6 against the Lakers and missed Game 7, which Los Angeles won 83-79.

With Perkins’ rehabilitation due to last well into the following season, general manager Danny Ainge signed Shaquille O’Neal and Jermaine O’Neal. Confident that they would remain healthy contributors, Ainge traded Perkins to Oklahoma City for Nenad Krstic and Jeff Green, but neither of them was able to remain in the lineup and the Celtics lost in the second round of the playoffs to Miami.

The trade looked even worse when Green was diagnosed with an aortic aneurysm, requiring surgery that put him out for this entire season. He is now a free agent.

Paul Pierce made his regular season debut registering 12 points, four rebounds, and five assists in 23 minutes of action.

“It felt good to finally get out there,” Pierce said. “I was expecting to be me and I don’t settle for anything less. I worked tremendously hard. I did a lot of things. I did what I could do coming into the game, as much as I could, other than practice. I just stayed focused.”

The Celtics shot 52.2% and made all 19 of their free throws.

The defense forced the Pistons to miss 13 out of their 16 three-point attempts.

Jermaine O’Neal led the way for the Celtics, generating 19 points to go along with seven rebounds and two blocked shots. He played a season-high 29 minutes.

It was a rare, big performance by Jermaine — so what was the difference?

“Playing extended minutes,” O’Neal said. “When you can get a rhythm, you can get a flow and you can get comfortable with what the team is doing. If you look at the first couple of games, I was in and out so fast that it was almost impossible to get any flow to the game.”

Brandon Bass collected 17 points in 22 minutes off the bench. It was his fourth straight double-digit scoring effort to start the season.

Ray Allen added 17 points. He is now averaging 20 points per game on 58.1% shooting and 58.3% from beyond the arc.

Next Game: Sunday at Washington Wizards, 6 ET.

UPDATE: Paul Pierce was in the starting lineup at small forward tonight against Detroit.

Boston Celtics scoring sensation Paul Pierce, who missed the first three games of the season with a bruised right heel, tweeted Thursday that he was “close very very close very.”

The Celtics play their home opener Friday night against another winless team –the 0-2 Detroit Pistons.

The last time Boston started the season losing three straight games — 2006-07.

With Sasha Pavlovic starting in Pierce’s place in each of the team’s games against New York, Miami and New Orleans — averaging 4.0 points and 1.7 rebounds a game — general manager Danny Ainge was hoping his most recent acquisition could contribute at the team’s thin small forward spot.

Pietrus Predicament: Ainge has told the Boston Globe that recently acquired small forward Mickael Pietrus is likely to make his Celtic debut by mid-January — he is about two weeks away.