The cost is high, but the alternatives were low, so Chauncey Billups will return to the Knicks. The 34-year-old point guard, plagued by injuries during his two months with the team, had his $14.2 million option for next season picked up Wednesday. That puts the Knicks over the current salary cap (almost certain to be altered by the upcoming labor agreement). It also means the Knicks have almost $51 million invested in three players next season, with Carmelo Anthony and Amar'e Stoudemire both due to earn more than $18 million. But they now have a bridge to the summer of 2012, when point guards Chris Paul and Deron Williams could become free agents. And if one hits the trade market next season, as 'Melo did this one, Billups' expiring contract is a valuable trade chip. Keeping Billups also bodes well for team president Donnie Walsh, whose autonomy in making personnel moves is an issue in a future that could be determined by the end of the week. He wanted to keep Billups, whatever the cost, and after owner James L. Dolan meddled in the deal that brought Anthony and Billups from Denver, Walsh got his way this time. "Chauncey, Amar'e and Carmelo are a great nucleus, as we continue to look to improve our team going into the off-season," Walsh said Wednesday in a team statement. "Chauncey is an extremely talented and experienced point guard - we are very happy to have him back." The alternatives, though, made his return almost a no-brainer. The Knicks could have bought out his option for $3.7 million to open up salary-cap space and find another point guard on a market with restricted free agents Aaron Brooks and Rodney Stuckey (whose current teams can match any offer they get) or unrestricted free agents such as J.J. Barea, T.J. Ford and Andre Miller.