School All-American Game. Walker was considered a lottery pick, but suffered the third knee injury in his career during a workout at the Golden State Warriors facility on June 15. However, he remained in the draft despite the injury, and was expected to have minor surgery in July that would keep him out for three to four weeks. Erden was not expected to join the roster this season, and was seen by general manager Danny Ainge as their first-round pick in 2009. Free agency The Celtics headed into the off-season with several free agents and tried to gather a group to repeat as the NBA Champions, with a key decision on unrestricted free agent James Posey, who, in a widely anticipated move, opted out of the second and final year of his contract with the Celtics on June 30, but stated that he wanted to return to the Celtics on a new contract. P.J. Brown, who made key contributions during the 2008 NBA Playoffs, was leaning towards retirement, and the status of restricted free agent Tony Allen remained uncertain after the first-round selection of J. R. Giddens, who was seen as a possible replacement. Later it was revealed that the Celtics did not extend a qualifying offer to Allen, making him an unrestricted free agent. The Celtics also hoped to keep unrestricted free agent Eddie House, and decisions were to be made on unrestricted free agents Sam Cassell and Scot Pollard. The Celtics were interested in small forward Corey Maggette as a replacement for James Posey, but Maggette signed with the Golden State Warriors on a much higher contract than the Celtics were able to offer, which added to the urgency to re-sign Posey. On July 11, the Celtics addressed their need for a backup center by signing Patrick O'Bryant to a 2-year, $3 million contract, after he had an impressive workout with the team a week earlier, and consequently ruled out the return of Scot Pollard and P.J. Brown. Eventually, James Posey signed with the New Orleans Hornets on July 16, since the Celtics were reluctant to offer him more than a three-year deal at the mid-level exception. Compensating for the loss of Posey, the Celtics re-signed Tony Allen to a 2-year, $5 million contract, and were also able to re-sign Eddie House to a 2-year, $5.6 million contract, using the mid-level exception only on House. On August 22,