These soon-to-be free agents could be dealt

With free agency in full swing, the Hot Stove is burning as we enter the holiday season. But as is the case each summer, there will be plenty of player movement next July as contenders begin to separate themselves from pretenders.
So while Manny Machado, Bryce Harper and Patrick Corbin dominate headlines at the moment, which players will be garnering the most attention seven or eight months from now?
Below are 10 players whose contracts are set to expire at the end of 2019. For the purpose of this exercise, any player with an opt-out clause or a 2020 option was not considered. Players including J.D. Martinez, Anthony Rizzo, Matt Carpenter and Edwin Encarnación might very well wind up on the free-agent market less than a year from now, though that won't be determined until the end of the 2019 World Series.

We went through the same exercise a year ago and hit on seven of 10, including each of the top five. In a sport where a .300 average can get you into the Hall of Fame, that's not too bad.
Without further ado, here's our list of 10 players who might be on the move, ranked from the most likely to be traded to the least.
Nick Castellanos
The Tigers are still in the relatively early stages of their rebuild, and while it's hard to believe Detroit will be able to move Miguel Cabrera or Jordan Zimmermann with their hefty contracts, Castellanos, who is heading into his age-27 season, is under control for only one more season and should bring back a nice return after posting an .831 OPS over the past three years. Castellanos earned $6.05 million last season and has one year of arbitration eligibility remaining.

Zack Wheeler
One of the more popular names in last summer's trade market, Wheeler remained with the Mets, who decided to hang on to both he and Noah Syndergaard to go with Jacob deGrom in the rotation. But if 2019 gets off to a rough start, the Mets will surely look to get something for Wheeler, a 28-year-old right-hander who pitched to a 3.31 ERA over 182 1/3 innings in 2018. Wheeler made $1.9 million in 2018, but should be in line for a nice raise in his final year of arbitration.

Billy Hamilton
Hamilton's consecutive seasons with a .299 on-base percentage hurt his value, which is largely based on his speed. But the Reds have entertained the idea of moving the center fielder before, and it's easy to imagine a contender wanting to add the 28-year-old for the stretch run next summer. Hamilton earned $4.6 million last season and is arbitration-eligible for the third and final time this offseason.

Mark Trumbo
Trumbo is in the final year of the three-year, $37.5 million deal he signed with the Orioles in January 2017. Trumbo hasn't come close to replicating his 47-homer season of 2016, but he hit 17 homers in 90 games last year, and teams are often seeking a power surge as the July 31 non-waiver Trade Deadline approaches. Baltimore is in rebuilding mode, so unloading the soon-to-be 33-year-old seems inevitable.

Justin Smoak
Smoak will earn $8 million -- a modest salary for a player who has hit 63 home runs with an .847 OPS over the past two years -- after the Blue Jays picked up his option. The Blue Jays could contend if things fall the right way for them this season, though it's just as easy to see Toronto struggle in the loaded American League East, which could prompt general manager Ross Atkins to become a seller. Should that happen, the soon-to-be 32-year-old Smoak would be among the prime candidates to be moved.

José Abreu
Abreu has been the subject of trade rumors for quite some time, but with one year of arbitration eligibility remaining, this would be the time for Chicago to move him if the club doesn't get off to a good start. Abreu's power bat would be welcomed by a number of teams, and although the White Sox are nearing the end of their rebuild, adding more young players for one they don't plan to re-sign makes sense. If he's not moved, Abreu could be a candidate for a qualifying offer next offseason.

Madison Bumgarner
The team-friendly extension Bumgarner signed with the Giants in 2012 is finally set to expire at the end of '19 after San Francisco picked up his $12 million option. The left-hander is coming off two injury-filled seasons across which he's made only 38 starts, throwing 240 2/3 innings, so he may need to get off to a good start to show teams he's healthy. But his contract is a bargain and every contender would love to add a top arm such as his, so if new Giants president of baseball operations Farhan Zaidi wants to add a haul of young talent to his system, moving Bumgarner next summer seems like a logical move.

Paul Goldschmidt
An All-Star in each of the past six seasons, Goldschmidt is among the premier hitters in the game. The D-backs have postseason aspirations after falling short in 2018, though the impending loss of Corbin and/or A.J. Pollock could impact the direction Arizona takes moving forward. It seems like a stretch that Goldschmidt, who will earn $14.5 million in 2019 after having his option exercised, would be traded before the season, but given how competitive the National League West is expected to be, GM Mike Hazen may have some tough decisions to make next summer.

Anthony Rendon
Rendon's future might depend on what happens with Harper this winter. If the Nationals spend big to bring Harper back to Washington, it might be a stretch for the club to re-sign Rendon to a sizeable deal when he hits the free-agent market next offseason. Max Scherzer and Stephen Strasburg are already locked into large deals through the next three seasons (four, in Strasburg's case), and with Rendon expected to get a nice raise in arbitration from his $12.3 million salary in 2018, his next deal will be costly. Unlike Harper, whom the Nats didn't want to trade last summer, Rendon could be moved to bring back some prospects to bolster the system.

Nolan Arenado
The idea of trading Arenado seems absurd given what he's meant to the Rockies, but the four-time All-Star figures to be the crown jewel of next year's free-agent market. If Colorado doesn't believe it can sign him to a long-term deal, moving him could become an option if the Rockies find themselves on the outskirt of the playoff race next summer. The Dodgers dealt five prospects for Machado last summer, so Arenado, who earned $17.75 million in 2018, would likely bring back a nice haul if the Rockies decided to deal him.