ORLANDO -- A blockbuster trade for young Diamondbacks star outfielder Justin Upton has become slightly more realistic in recent days as several teams -- mostly from the American League, and prominently including the Red Sox -- have shown interest but an Upton deal remains far from a certainty.

Several teams have suggested to Arizona to look over its roster and return with proposed asking prices. Boston, which seeks to add a prominent outfielder and prefers young players, has been among the more aggressive teams so far, and the Diamondbacks are believed to want young outfielder Jacoby Ellsbury and top young reliever Daniel Bard, among others, included in any Upton bid. But there are said to be as many as 15 teams showing some level of interest in Upton, a 23-year-old outfielder who hit .273 with 17 home runs and 69 RBIs.

The Diamondbacks have just about ruled out trading such a top young player to any team and their own division (the NL West) and would greatly prefer to deal with AL teams. Dealing a young player with as much talent as Upton is a great gamble, but the Diamondbacks are willing to consider just about anything as they try to recover from a rough 2010 season in which they went 65-97 and in a difficult division that includes the world champion Giants.

The Yankees are among other teams to show interest in Upton, but while new Diamondbacks general manager Kevin Towers, who consulted for the Yankees last year before being hired by Arizona, likes several of their players, it's less certain Arizona matches up with them. The Marlins are among other teams to show interest.

One opposing executive called the asking price on Upton "ridiculous.'' But considering how high the prices may become in the free agent market, a young player with this type of ability who has a more reasonable contract (five years left on a six year, $51.25 million contract he signed last March) will look enticing to several teams. Top free agent outfielders Carl Crawford and Jayson Werth both seek deals for at least $120 million. Boston has been seen as a likely landing spot for Werth especially.

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