In this photo taken by AP Images for Excedrin, six-time...

In this photo taken by AP Images for Excedrin, six-time NBA All-Star and New York Knicks basketball player Amar'e Stoudemire, right, shoots hoops with Walt Arnett, 29, of Lexington, Ky., winner of the Excedrin "What's Your Headache?" contest, after a ceremony at Chelsea Piers. (June 15, 2011) Credit: AP

Amar'e Stoudemire is still dealing with a backache.

"It's still a little sore, but it's better today," he said Wednesday at a marketing event at Chelsea Piers for a Facebook campaign organized by the pain medicine Excedrin whose slogan, coincidentally, asks: What's your headache?).

Stoudemire strained a muscle in his lower back during warmups before Game 2 of the Knicks' first-round playoff series with the Celtics. The injury limited him to less than 18 minutes in that game and hampered him for the rest of the series, which ended in a four-game sweep. Six weeks later, Stoudemire admitted the back was "still pretty tight" but added that he has been able to work out regularly.

He put up a few jumpers and even made a few moves to the basket for a photo op and moved well for someone in a suit. "It's a strained muscle," he said. "It takes a while to get that motion back."

He and Chauncey Billups (strained tendon in his left knee) went down early in the series, which gave the Knicks little chance to compete against the veteran-laden Celtics. Billups recently had a follow-up MRI on the knee, which showed no further damage. Billups is expected to begin his offseason regimen in July in Los Angeles.

Stoudemire also will be in Los Angeles, most of this offseason and said he already has talked with Carmelo Anthony about getting their Knicks teammates together for workouts.

With the strong possibility of a lockout looming, it may be awhile before the group returns to New York for training camp.

"We're all going to try to meet up in L.A., to start training maybe mid-July," he said.

The success of the Miami Heat's Big Three, which came within two wins of the NBA title in their first season together, provided reason for Stoudemire to believe the Knicks aren't that far away, either.

"Whenever you have two great players together," he said, "you have an opportunity to do something special . . . The key to the factor is, you have to get better defensively.''

Mike D'Antoni plans to address that issue by hiring a defensive assistant coach.

This is yet another critical offseason for the franchise on many levels, starting with the NBA's new collective bargaining agreement. A revised system, especially if the league gets the hard cap it is seeking, could cause a dramatic change in plans for the Knicks, who are hoping to add one more star player (Chris Paul, Deron Williams), before 2012.

Then there is the question of who will replace Donnie Walsh at the helm. Walsh's sudden departure came as a surprise to Stoudemire.

"I was a little shocked; I had no idea," he said. "But after talking to Mr. Walsh, he felt positive about the decision he was making, which made me feel positive about it."

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