Time to clean house

WALTHAM -- The infections that have sidelined Paul Pierce (left middle finger) and Delonte West (second toe on right foot) were no coincidence. The Celtics announced yesterday the "organization has sustained a small bacterial infection issue."

The bacterial infection is Methicillin Resistant Staphylococcus Aureus, commonly known as MRSA. The Celtics are "aggressively undertaking steps to test each of our basketball staff members and players" and "are professionally cleaning our facilities in Waltham and at the TD Banknorth Garden," according to a statement released by the team. The practice facility will be sanitized from top to bottom this weekend.

The Celtics educated the team about MRSA before practice yesterday.

"I'm glad [trainer] Eddie [Lacerte] and [team doctor Brian McKeon] thought it was strange that basically they were tiny cuts and two guys have pretty bad infections," said coach Doc Rivers. "[The facility] is being cleaned out because they can't take any chances."

Rivers said no other players have shown symptoms. Pierce, who had half his nail removed Tuesday to treat the infection, returned to practice after missing the final two exhibition games.

Allen goes fourth

Tony Allen was the happiest person at the training facility. With the Celtics exercising his fourth-year option, Allen looked and sounded like a newly confident player.

"Now, I can relax," said Allen. "It doesn't mean you stop working or anything like that. I still have a lot of work to come. I was always told hard work is going to pay off."

Allen said his game is improving as he gains strength in his right knee after surgery during the 2005 offseason.

"I'm doing whatever Coach needs me to do out there," said Allen. "[My knee] is coming along fine. I like my progress."

Healthy outlook

Brian Scalabrine (separated left shoulder) returned to practice and Rivers reported he "looked great." With the exception of Theo Ratliff (sore lower back) and some minor soreness for Pierce and West, the Celtics appear healthy with Opening Night less than a week away. "There's no injury update except for Theo, and he says it's feeling a little better," said Rivers. "It wasn't a long practice. We didn't do much, but everyone looks good. Scal plays physical like he plays, and that was good because he's not worried about his shoulder." . . . Michael Olowokandi, who made the final cut, missed practice to visit his daughter, who has a mild case of pneumonia . . . Al Jefferson was launching 3-pointers after practice. He made one, though his right toe might have been in front of the arc . . . Brian Grant, who was waived Thursday, retired because of chronic knee problems.

Material from the Associated Press was used in this report. Shira Springer can be reached at springer@globe.com.