The market appears to be heating up for free agent pitcher James Shields, and the suddenly free-wheeling Miami Marlins are reportedly in on the chase.

Coming off signing outfielder Giancarlo Stanton to the richest contract in MLB history, a 13-year, $325 million extension that includes a no-trade clause as well as an opt-out clause for Stanton, the Marlins seem ready to bolster the pitching staff to take advantage of their cavernous ballpark.

Shields' stock took a bit of a hit after a mostly unsuccessful postseason in which he pitched to a 6.12 ERA over 25 innings, but for the regular season he was a workhorse No. 1 starter. He was also a mentor for some of Kansas City's young pitchers, and the Marlins projected 2015 rotation doesn't have a single player less than 28 years old.

Shields is 32 years old, but isn't showing many signs of decline. Shields was 14-8 with a 3.21 ERA in 34 starts; it was the eighth straight season he made at least 31 starts.

While the Royals aren't expected to make much of a run to keep Shields, the Marlins aren't alone in coveting his services. Fox Sports' Ken Rosenthal reports the Arizona Diamondbacks are expected to gun for the right-hander, and even tried to acquire Shields and Wade Davis (the same two involved in the Royals trade) two years ago.

That trade would have sent outfielder Justin Upton to the Texas Rangers and netted the D-Backs the two hurlers.

The problem for Arizona is payroll, wrote Rosenthal. After dealing with arbitration-eligible players, the Diamondbacks will be up to about $90 million, and their peak payroll figure is about $110, meaning fitting Shields' expected salary in will be difficult.

Rosenthal said to accommodate adding a potential ace this offseason the D-Backs are willing to trade away catcher Miguel Montero, infielder Aaron Hill, and outfielder Cody Ross.