While Pierce has received introductory inquiries from "a few" other teams, Boston is the only team he's currently engaged with, sources told ESPN.com.
Pierce joined the most anticipated free-agent class in NBA history by notifying the Celtics that he was opting out of his contract Tuesday and walking away from next season's $21.5 million salary.
Since that decision, though, Celtics coach Doc Rivers has pledged to stay on the bench for at least one more season, giving Boston management increasing confidence that it will soon come to terms with Pierce on a new deal.
Multiple sources with knowledge of the team's thinking told ESPN.com on Wednesday that the team believes it will secure a verbal agreement from Pierce before July 8, which is the first day players and teams can execute new contracts.
Pierce's name has scarcely been mentioned in the buildup to the summer 2010 free-agent bonanza because, as with Dallas' Dirk Nowitzki, most rival executives believe that the Celtics would never allow the 2008 NBA Finals MVP -- who has maintained for some time that he wants to retire a Celtic -- to leave the only team he's ever known.
Pierce, though, has not discouraged outside interest, even though it appears he is not yet prepared to talk with other teams.
The most Boston can give Pierce is a four-year deal worth a maximum of $96 million, although the Celtics are naturally hoping to re-sign him for less than that, with Pierce's 33rd birthday approaching in October and Boston hoping to start restoring financial flexibility to infuse the roster with some youth. The maximum Pierce could receive from other teams is a four-year deal worth $93 million.
It seems unlikely that Pierce would receive a contract longer than four years, because a fifth season would begin when Pierce was 37, which would have costly salary-cap implications for any team signing him because of the NBA's over-36 rule.
Pierce, though, is eligible to secure a rare no-trade clause if he stays with the Celtics. Players with at least eight years of service time and at least four seasons with the same team can negotiate a no-trade provision into new contracts, which would not have been possible had Pierce agreed to an extension to his current contract before Thursday.
If it winds up re-signing Pierce for less than the maximum, as the team hopes, Boston will inevitably wind up pleased that its captain took this step. Any amount below the $21.5 million that Pierce was scheduled to earn in 2010-11 will net a savings of twice that amount because the Celtics are a luxury-tax team.
Marc Stein is a senior NBA writer for ESPN.com.