Paul Pierce is at a career crossroads, and he should take the direction that leads out of Boston.The truth about “The Truth” hurts, but the fact is that there is nothing more Pierce can accomplish in Boston, and nothing more he will accomplish should he stay. It’s time to take the pragmatic route and join another team.Should he stay, he’ll be part of a familiar scenario for Celtics fans with long memories: A superstar on the downside of his career leading the team toward the downside of a dynasty. The “Big Three” of the 1980s overstayed their welcomes worse than weekend houseguests – OK, maybe not Larry Bird – and poor playoff results after 1988 proved this.If Pierce wants another title to solidify his reputation as one of the greats, he should realize that his best opportunities may lie elsewhere. Boston is a team in flux, with Rasheed Wallace likely retiring, Kendrick Perkins hurting, and Ray Allen also an unrestricted free agent. And Pierce’s skills are also at a transition point. He can still score, but not as frequently. He shot a combined 11-for-29 over the last two games of the NBA Finals.Pierce’s best move might be for “The Captain” of the Celtics to become “The Lieutenant” on another team. This, too, is a familiar scenario in NBA annals: The former superstar with one team opting for a reduced role on another in hopes of one more ring. Pierce’s nemesis, Ron Artest, tried it this year with the Lakers and succeeded; Wallace attempted it with the Celtics and failed. For Pierce, it’s a strategy worth trying.There is a lot for Pierce to be proud of in Boston. He stuck with the team from the dismal days of Rick Pitino ? to the hopeful seasons of Jim O’Brien ? to the initial frustration and subsequent renaissance under current coach Doc Rivers. He showed everyone who came to watch the duck boats in 2008 the positive side of one player sticking with one team when certain other superstars seem only too happy to ditch the squad that drafted them (are you reading this, LeBron?). There is something to be said for staying rooted in a world that seems ever more uprooted with all the foreclosures and firings out there.Trouble is, there’s a difference between staying loyal and staying in one place too long. Pierce’s reputation in Boston might suffer if he stays and posts more nights like the 5-for-15 shooting effort against LA in Game Seven. The fans who once cheered might now boo ? and that’s no way for “The Captain” to go out.In “Henry V,” Shakespeare alluded to the frustration faced by one of history’s titans, Alexander the Great, when he ran out of worlds to conquer and had to sheath his sword “for lack of argument.” Paul the Great has similarly achieved pretty much every item on the checklist at TD Garden. If he wants to enhance his resume further, he should look elsewhere.Rich Tenorio is The Item’s sports copy editor.