The Giants and Pirates have had recent contact regarding a trade that would send Andrew McCutchen to San Francisco, a source told MLB.com, although a deal is not imminent and multiple barriers remain.The teams have had dialogue regarding McCutchen since early in the offseason, without producing any apparent breakthroughs. That

The Giants and Pirates have had recent contact regarding a trade that would send Andrew McCutchen to San Francisco, a source told MLB.com, although a deal is not imminent and multiple barriers remain.

The teams have had dialogue regarding McCutchen since early in the offseason, without producing any apparent breakthroughs. That is not surprising, as the Pirates also proceeded deliberately in their McCutchen trade discussions last offseason.

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Meanwhile, the Giants are reluctant to part with top prospects for McCutchen, after giving up highly regarded infielder Christian Arroyo in last month's trade with the Rays for Evan Longoria .

Outfielder/first baseman Chris Shaw, right-hander Tyler Beede and outfielder Heliot Ramos are the Giants' top three prospects, per MLB Pipeline. One source said the Pirates are asking for at least one of those three in any McCutchen trade with San Francisco.

The Pirates are well-positioned to seize upon the slow pace of the free-agent market by trading McCutchen, ace pitcher Gerrit Cole and the versatile Josh Harrison, all of whom have generated interest from other teams in recent weeks.

The Giants, who finished last in the Majors in home runs in 2017, have been searching for a power-hitting outfielder since the offseason began. They agreed with the Marlins on a trade for Giancarlo Stanton , before Stanton used his no-trade rights to block the deal.

McCutchen would be a much more straightforward move. He lacks a no-trade clause and is due to earn $14.5 million in 2018, before becoming a free agent. McCutchen is coming off a season in which he hit 28 home runs, the second-highest total of his career.

It's unclear if the Giants believe they can acquire McCutchen and Cincinnati center fielder Billy Hamilton , who they've had extensive trade conversations about this offseason as well. In combination with the Longoria trade, the acquisitions of McCutchen and Hamilton would substantially weaken a farm system already being revamped under new vice president of player development David Bell.

Giants general manager Bobby Evans has spoken publicly about a need to improve his team's defense in center field. Hamilton, 27, has been one of the Majors' top defensive center fielders the past several seasons. McCutchen, 31, was better in right field (in a small sample) than center last year, according to defensive metrics.