Ray Allen will be 37 years old next season and he is undergoing surgery on Wednesday to remove bone spurs which bothered his ankle during the 2012 NBA Playoffs. But he's also set to be one of the more desirable free agents on the market, at least for contenders looking for one piece to push them over the top.

Three teams expected to show major interest in Allen this summer include the New York Knicks, Los Angeles Clippers and Miami Heat. According to a report from ESPN New York's Jared Zwerling, the Clippers and Heat could be Allen's top options as of now.

Via Zwerling:

If the Celtics don't pan out for Allen, Sports Illustrated's NBA writer Chris Mannix was told that the Knicks and Heat are at the top of his list. But a source very familiar with Allen's situation told ESPNNewYork.com that the Heat, as well as potentially the Clippers, will be more attractive to the five-time All-Star in the offseason because they're top teams that can offer more than the veteran's minimum of $1.4 million. That will likely be the Knicks' spending limit for free agents.

The Celtics will likely want to retain Allen. With his shooting, he would be a perfect sixth man behind the defensive-minded Avery Bradley. But he's going to test the market, and he wants to land somewhere his name won't be mentioned in trade rumors at every deadline.

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