The Marlins have already traded two-thirds of their outfield this winter, and they are listening to offers to possibly complete the trifecta. Though not coming off an MVP season like Giancarlo Stanton or a .924 OPS campaign like Marcell Ozuna, Christian Yelich is the most valuable trade chip of the three in terms of the prospect pieces that can be brought back to the rebuilding Fish because of the team-friendly nature of his contract.
Yelich is under team control for a grand total of $58 million for the next five seasons (counting a $15 million option for 2022). That's bargain-bin stuff for a potential superstar who brings a sweet swing and good defense and baserunning.
So ... what's his trade value?
One comparable to work off of here is the Adam Eaton trade from last winter. It's not a perfect comparison, as Eaton was entering his age-28 season, whereas Yelich is entering his age-26 year. But consider this: Thanks to stellar defense that earns plaudits from a variety of advanced metrics, Eaton was also coming off a 6.2-bWAR season, while Yelich has been worth an average of 4.2 bWAR over the last four years.
And like Yelich, Eaton came with five years of what was considered team-friendly control. Eaton landed the White Sox three of the Nationals' top 10 prospects, as determined by MLB Pipeline at the time -- Lucas Giolito, Reynaldo Lopez and Dane Dunning (Giolito and Lopez were both in the Top 100 overall).
The Marlins recently dealt Ozuna, who is two years away from free agency, to the Cardinals for four prospects, only two of whom (Magneuris Sierra and Sandy Alcantara) ranked in the Cards' Top 10 and none of whom ranked in MLB Pipeline's Top 100 overall. The Fish will certainly be looking to exceed that return in a trade for Yelich, given the years of control involved.

How many teams are interested in Yelich? It would be easier to list the teams that don't have a need for a controllable, impact bat like this. But here are 10 teams rumored to have shown interest and what it might take to land him.
Consider these starting points. Perhaps another player would be added to these concepts to round out a deal, especially with so many teams involved. But hopefully this provides a general idea of how a given team might motivate the Marlins to make a deal.
Astros: OF Kyle Tucker, RHP Corbin Martin, OF Drew Ferguson
The Astros absolutely, positively would not want to surrender Tucker … which makes him the perfect centerpiece! I'm generally leaning toward outfielders as the prime target in these proposed swaps, given the way the Marlins have raided that particular area this winter, and the Astros have one of the most highly prized outfield prospects in the game in Tucker (No. 8 overall on MLB Pipeline's Top 100). With that A-grade prospect involved, the defending champs round out the deal with two other guys from their Top 30 and slot Yelich into left field.

Blue Jays: OF Anthony Alford, SS Logan Warmoth and RHP Conner Greene
The Blue Jays are simultaneously trying to win now while acknowledging that their roster age will soon require a significant transition. Yelich serves those dual purposes and just so happens to fill a glaring need in the outfield. The trick would be landing him without surrendering either of two infielders with famous fathers -- Vladimir Guerrero Jr. (No. 4 overall on MLB Pipeline's Top 100) or Bo Bichette (No. 26). And anyway, trading Guerrero in the year his dad might go to the Hall of Fame just feels like an invitation to bad karma. But in keeping with our outfield emphasis here, the Blue Jays could potentially build something around Alford (No. 44 overall), who could soon succeed Yelich as a legit top-of-the-order presence.
Braves: LHP Kolby Allard, RHP Ian Anderson and OF Christian Pache
Yelich is the perfect piece to help the Braves shift to the next phase of their rebuild. But the difficulty here -- beyond the intra-division factor -- is that the Braves are simply not going to surrender their top prospect, outfielder Ronald Acuna, at this stage of the rebuild. So this deal would likely have to be more pitching-rich, and, given the sheer mass of high-quality arms in the Braves' system (Allard and Anderson are two of six pitchers they've got in the Top 100 right now), that's definitely doable.

Dodgers: OF Alex Verdugo, C Keibert Ruiz, RHP Jordan Sheffield
No, the Dodgers didn't acquire a certain Marlins outfielder from the L.A. area earlier this offseason, but they can still get this one. The Dodgers are undoubtedly deep, but Yelich's contract more closely aligns to the front-office philosophy of flexible roster construction than Stanton's did. A Marlins team that has gutted its outfield gets a Major League-ready piece in Verdugo, while Ruiz and Sheffield are high-grade prospects who are a couple years away.

Giants: OF/1B Chris Shaw, RHP Tyler Beede, OF Heliot Ramos, LHP Andrew Suarez
The Giants' need for Ramos -- especially in light of the way he fits a budget pushing up against the luxury tax threshold -- could not be more clear. But this club just dealt Christian Arroyo (in the Evan Longoria trade) from an already-thin system (they don't have anybody left in the Top 100), making it appear doubtful they'll have the capital to acquire Yelich. But here's a ballpark swing at it with not three but four of their top 10.
Nationals: OF Michael A. Taylor, OF Victor Robles, C Pedro Severino, RHP Erick Fedde and INF Yasel Antuna for Yelich AND C J.T. Realmuto
Among the Marlins' trade chips, Realmuto is probably the more pressing need for the Nats behind the plate, but the Nats have been rumored to have shown interest in both guys. So let's go for both (and go for broke) here. Yelich is insurance should Bryce Harper depart at year's end, and Realmuto solves a position in which Matt Wieters didn't deliver last year. That's how the Nats can justify giving up Robles, the No. 4 overall prospect in the game, per MLB Pipeline (this deal allows them to keep Juan Soto, who is No. 37 overall). This would be a ton of viable talent headed to Miami, which is the whole point, and it's a huge price to pay for a Nats team that desperately needs to advance in 2018. So that feels right.

Phillies: OF Nick Williams, OF Mickey Moniak, C Jorge Alfaro
The Phils already have a logjam in the outfield thanks to the Carlos Santana acquisition, moving Rhys Hoskins to left, and this admittedly does nothing to solve that. But Yelich could surely help speed up their rise in the National League East. Sorry, Marlins fans, you're not getting Hoskins. But Williams slides right into the Marlins' outfield, and Moniak, the No. 1 overall pick in 2016, is the key to the deal, keeping the Phils from having to give up prized right-hander Sixto Sanchez or prospects Scott Kingery and J.P. Crawford, who could both be in the infield this year. Moniak and Alfaro both rank in MLB Pipeline's Top 100.
Rangers: OF Leody Taveras, 1B Ronald Guzman and LHP Cole Ragans
Yelich is versatile enough to handle the Rangers' need in center field, and he certainly fits their budget. The switch-hitting Taveras is a ways away from the big leagues, but the five-tool talent is certainly a worthy headliner for the Marlins, who also acquire two other top 10 guys from the Rangers' list here.
White Sox: OF Blake Rutherford, RHP Dylan Cease and C Zack Collins
The beauty of Yelich's contract is that it slides in as well on teams still building toward postseason viability as well as it does clear contenders for 2018. It seems reasonably clear that the White Sox aren't going to deal any of their top three prospects -- Eloy Jimenez (acquired in the Jose Quintana trade), Michael Kopech (acquired in the Chris Sale trade) or Cuban signee Luis Robert. But the Sox's system is so deep that it includes three other guys in MLB Pipeline's Top 100, and the Marlins get two of them (Rutherford and Cease) here, with Collins going back to Miami, where he starred with the Hurricanes.