NASHVILLE, Tenn. -- There aren’t many chairs left as the center field dance slows down, and as Michael Bourn looks for a home, the Phillies and Mariners continue to show strong interest, according to CBSSports.com sources.

The Mariners are looking for an impact bat, preferably a middle-of-the-lineup hitter to boost their anemic offense. Bourn is not that, but he could become their top target if Josh Hamilton winds up being too expensive for Seattle.

The Phillies, meantime, are badly in need of outfielders and Bourn would be a strong upgrade over the man who opened last season in center field for the Phillies, Shane Victorino.

“It’s rare in baseball you see someone who dominates at certain things,” Bourn’s agent, Scott Boras, said during his first public appearance here late Wednesday afternoon. “You see it sometimes in catching. Michael by far is the best defensive center fielder in the game.”

Bourn, 29, is speedy and versatile. He will steal bases and ignite an offense, but he will not knock the ball out of the park. He batted .274/.348/.391 last year with nine homers, 57 RBI and 42 steals.

Bourn led the NL in steals for three consecutive seasons (2009-2011) before ranking second to the Padres' Everth Cabrera last summer.

“I think when you look at his defensive runs saved over the last four seasons he’s in the mid-60s, and many of the players who have signed are in the minus-30s or minus-20s or zero. He offers a team almost 80 or 90 more outs than the quality center fielders. He’s just that good.

“He’s somebody that a lot of teams are obviously looking into. Then you add to that the fact that he scores 95 runs, hits leadoff, averages 40 stolen bases and has led the league in stolen bases … he’s a franchise guy.”

The Braves, who acquired Bourn from the Astros in 2011, had hoped to retain him but ultimately decided he would be too expensive. Instead, Atlanta earlier this winter went proactive, signing free agent B.J. Upton to a five-year, $75 million deal.

The Nationals figured to be in the Bourn market, too, but they traded for center fielder Denard Span from the Twins.

The Red Sox were a potential suitor, but they agreed to terms with Victorino on Tuesday on a three-year, $39 million deal.

Hamilton still very much could affect Bourn, which is part of the reason why the Bourn negotiations appear to be going very slowly. The Mariners are engaged in talks for Hamilton, and Red Sox general manager Ben Cherington and manager John Farrell reportedly met with Hamilton in Nashville on Monday.

While the general thinking is that the Victorino and Mike Napoli (three years, $39 million) signings would preclude the Red Sox from romancing Hamilton, they have not said that they’re done for the winter. There is a very real possibility that they could still make a run at him and trade Jacoby Ellsbury to clear room.

If that scenario were to play out, Ellsbury likely would attract interest from some of the same clubs who now are considering Bourn.