As teams across the league approach the 50-game mark, the league's power structure for the season is beginning to take shape. Plenty of teams are on the cusp of turning their focus towards retooling for the future. With about a third of the season's games under our belt, here are five MLB teams that will be the biggest sellers come the trade deadline.

5. Cincinnati Reds

Chicago Cubs v Cincinnati Reds

The Reds are the only sub-.500 team in the NL Central, practically assuring that they'll sell at the deadline. Slugging second baseman Scooter Gennett is all but assured a one-way ticket to a contender once he gets healthy, and the failed experiment with Yasiel Puig could at least end up netting them a mid-level prospect.

4. Seattle Mariners

Minnesota Twins v Seattle Mariners

General manager Jerry Dipoto is known for his drive to swing trades. As the Mariners enter yet another rebuild, some intriguing talents, such as starter Marco Gonzales, have emerged on their team this year that will almost certainly be shipped out to contenders in exchange for prospects to bolster an already-talented farm system.

3. Detroit Tigers

Oakland Athletics v Detroit Tigers

Talent abounds in Detroit as they continue their tanking process. Veterans Nicholas Castellanos and Josh Harrison are both on expiring contracts, and will inevitably be dealt come July 31. Closer Shane Greene, who has quietly amassed an AL-leading 15 saves this year, will also likely be on the block.

2. San Francisco Giants

San Francisco Giants v Arizona Diamondbacks

Madison Bumgarner alone earns the Giants a spot on this list. Add in the likes of Brandon Belt, Will Smith and Tony Watson, and you've got yourself a hefty amount of trade chips. Already 10.5 games out of first in the NL West, it seems inevitable that the Giants go for a full tear-down this summer.

1. Washington Nationals

New York Mets v Washington Nationals

2019 has been a catastrophic failure for the Nationals. A team that hoped to compete for at least a Wild Card spot has struggled to gain any momentum, and with a stockpile of talent in the likes of Max Scherzer, Anthony Rendon and Sean Doolittle, the Nationals are destined to host the biggest fire sale we've seen in recent memory.