James Shields free agency preview

James Shields can make himself a very rich man if he keeps pitching like he has during the past two months. He was already set to make millions this winter, when he'll hit the free agent market, but a recent stretch has the Royals ace in position to really cash in during the upcoming offseason.

The right-hander has a 2.11 ERA since he tossed seven shutout innings against his former club, the Tampa Bay Rays, on July 7. During that 13-start span, Shields has lowered his ERA by 80 points while helping the Royals jump into first place in the AL Central. (They've since fallen back into second, despite Shields' recent dominant outings against the Yankees and division-leading Tigers.)

Shields has certainly been through his share of highs and lows this season (and throughout his career), but he's come out through it all as an ace who is capable of eating up quality innings. He'll have some competition on the market in All-Star starters Max Scherzer and Jon Lester, but that shouldn't keep Shields from receiving a deserving contract that will likely put him on a contending team as he hits the final years of his career.

Let's see how Big Game James got to where he is now, then we'll talk about some possible destinations.

Where he's been

Shields' best season came in 2011, when he performed one of the more remarkable single-season turnarounds in recent history. He hasn't quite been able to replicate that success, but his penultimate season with the Rays three years ago established Shields as one of the game's best and most durable pitchers.

After posting a 5.18 ERA, allowing 246 hits in 203.1 innings and losing 15 games in 2010, Shields did a complete and utter 180. He essentially flipped his hits and innings totals from the previous season, lowered his ERA to 2.82 and, perhaps most importantly for his value today, pitched 11 complete games. That latter total made up exactly one third of Shields' starts that year, and he also pitched shutouts on four of those occasions.

Shields is an elite pitcher, and most parts of his game have reflected that since he started dominating in 2011. He shows good control, having ranked in the top 20 in BB/9 in each of the past four seasons. He also has a history of posting good strikeout totals, despite 2014 being a down year in that sense. (Shields averaged just under 215 strikeouts per season from 2011 to 2013.)

But the one issue that Shields hasn't quite been able to solve is keeping the ball in the park. He's gotten significantly better since topping out at 34 homers allowed in 2010, but his HR/9 rate has stagnated at right around 1.0 since 2011, which is just over the league average. Still, looking back at Shields' 2010 season, in which is led the league in hits, earned runs and homers allowed, the improvement is evident.

Where he is now

Shields' incredible show of durability in 2011 proved to be a bit of an anomaly, as he's only completed six of his 98 starts since that year with 11 CGs in 33 outings. But he's still a perennial lock for 200 innings, and with three starts left in the season, he could post the second-highest innings total of his career.

Another positive of Shields' season is his vastly improved control. He's always been good at limiting his walks totals, but this season the right-hander has walked 27 fewer batters than he did last year, to the tune of a 1.8 BB/9 rate. That's his best total since 2008, and it has led to his highest K/BB ratio since his first full season, even though Shields is striking out batters at his lowest rate since 2009. He's throwing quality strikes and fewer balls, allowing him to go deep into his starts while allowing the Royals bullpen to stay fresh for other games.

Though he only has one complete game in 2014, Shields has gone seven or more innings in 17 of his starts, and he's failed to make it through six only four times. As a result, the Royals have won 19 of the right-hander's 31 starts.

On top of all that, Shields has his lowest ERA since 2011, and his ERA+ ranks as his third-best single-season total. But he has appeared a little too hittable throughout the season, allowing 203 knocks in 207.1 innings, and his strikeout rate of 7.1 per nine innings is the lowest since 2009.

But Shields' recent success might have a few teams turning a blind eye toward those warning signs. He has been lights out in September, living up to his nickname with two big game performances against the Tigers and Yankees, combining to allow five hits and a walk across 15.1 shutout innings. He also tossed a complete-game shutout against the Giants in August, one start after he dominated the A's over eight strong innings. Overall, he has eight quality starts in his last nine outings with a sub-three ERA in both July and August.

Where he's going

Shields has performed like an ace for the past two seasons, and he gets plus points for his durability and general consistency over the better part of a decade. That means he'll earn top dollar on the market, and keeping that in mind, we should really only consider a select few teams—the ones with big checkbooks—as possible suitors for Shields. (There's one notable exception; more on that later.)

At first glance, the Red Sox are the most obvious club, with their big payroll and clear need for an upgrade in the rotation. The Sox could make a push for Lester, who they traded back in July, and the left-hander has stated his willingness to return to Boston. But if Lester signs elsewhere, expect the Sox to go all-in on Shields, especially for the purpose of keeping him away from other teams in the division.

Speaking of which, any discussion about possible destinations for a top free agent wouldn't be complete without the Yankees, who could be looking for a starter this offseason given the possible departure of Hiroki Kuroda and the struggles of CC Sabathia.

If the Yankees 2015 payroll is in line with what it's been over the past few seasons, GM Brian Cashman won't have much leeway this winter when it comes to signing big-name free agents. The Yanks already have upwards of $170 million committed to their payroll for next season, on top of re-signing players with expiring contracts like closer David Robertson.

But if the Yankees can shell out some extra cash (a very viable possibility), Shields would be a prime candidate to move to New York. It's anyone's guess as to whether Sabathia will bounce back from his tough 2014 season, and the team clearly could use pitching help given the mediocre results this season. Masahiro Tanaka, Michael Pineda and Brandon McCarthy (if he re-signs) likely won't be enough for guide the Yankees to a postseason berth, and the team will have to make another move or two if it's serious about contending next year.

Overall, Shields to the Yankees is a bit of a longshot given the team's already committed payroll, but we've learned time and time again to never count the Yankees out of any bidding for top FAs.

Interestingly, the Marlins might be one of the top contenders for Shields as well. With the news that the team is preparing to offer outfielder Giancarlo Stanton a huge contract this winter, that seems difficult to believe, but an extension of the slugger might actually increase the team's chances of signing a top pitcher like Shields.

That's because, as MLB.com's Joe Frisaro reported in August, the Marlins are interested in building a team around Stanton, and that starts with bringing on another elite pitcher to help cope with Jose Fernandez's absence during the first half of the season.

Frisaro specifically suggested Shields in his article, and the signing isn't as far-fetched as you'd think. With the Marlins payroll potentially jumping by around $30 million, the team could conceivably give Stanton the salary he deserves and still have room to bring on Shields. Plus, the right-hander would likely welcome a move to the NL East after spending the majority of his career in two very hitter-friendly divisions.

Shields' fate might depend largely on other deals, like whether Lester returns to Boston or whether the Marlins can ink Stanton to an extension. But this early in the game, the Red Sox are clearly the most likely destination for Shields this offseason.