Bill Walker, F, 6-6, Kansas State -- May be a diamond in the rough if his knee problems are solved. Acquired in draft night deal from Washington for cash.

Semih Erden, C, 6-11, Turkey -- Tough inside player who has one year left on his Turkish League contract. A pick for the future.

BIGGEST NEEDS: The Celtics would like to solidify the center position. Kendrick Perkins is still their guy, but he missed Game 5 of the Finals with a left shoulder problem that has dogged him in the past. Even assuming he is fine, they'd like to be more certain of who backs him up. Scot Pollard had the job before injuries got to him. Then veteran P.J. Brown came in late and was tremendous. But will he retire?

FREE AGENT FOCUS: The Celtics didn't get to keep James Posey, but Tony Allen and Eddie House are staying. Patrick O'Bryant was signed as a backup center, but the club is still looking for a veteran in the P.J. Brown mold. F Darius Miles was signed.

PLAYER NOTES:

--C P.J. Brown isn't planning on being in anyone's training camp, but the veteran center is saying he's not necessarily retired. It is possible Brown will do as he did last season and join a club in January or February.

--C Kendrick Perkins has been working hard in the offseason to avoid a repeat of left shoulder problems that caused him to miss Game 5 of the NBA Finals. Perkins has had problems with the shoulder in the past.

--F Glen Davis has been a fixture in the Boston area this summer, doing a great deal of community relations work in addition to much conditioning. Davis wants to be quicker on defense this season.