Billy Hamilton has been in the big leagues for nearly five full seasons now, and it's become clear that he's never going to be even an average Major League hitter. In over 2,500 plate appearances, he's put up a line of .245/.299/.331, which is one of the 10 weakest lines of qualified hitters since 2014, per wRC+. It's worse than 96 percent of hitters with as many plate appearances in the last 50 years. With Hamilton's salary likely to go north of $5 million in arbitration next offseason, he's very possibly a non-tender candidate.

You wouldn't think that a player we've described like that would be someone that contenders would want to go after at the Trade Deadline. But allow us to argue the opposite: Hamilton's breathtaking speed and skill on the bases and in the outfield would make him a fantastic secret weapon down the stretch and in October for more than a few contending teams. Remember how the Royals got value from Jarrod Dyson and Terrance Gore in 2014-15?

We probably don't need to express to you how elite Hamilton's speed is, but we'll do it anyway. His 252 steals since 2014 are the most in the Majors, ahead of Dee Gordon's 237, and according to FanGraphs's "Base Running Runs," which also accounts for taking extra bases, he's first over Mookie Betts by just a ton.

That elite speed has lent itself to some game-changing defensive skills. Hamilton is tied for seventh in outfield Defensive Runs Saved since 2014. That's backed up by his position in Statcast™'s Outs Above Average metric, which measures range and plays made (excluding arm, currently, for the three years it's available.

Hamilton Outs Above Average rankings in 2016-18

2016: +23, second best (of 208)

2017: +13, eighth best (of 206)

2018: +14, second best (of 174)

Hamilton has been so good on defense and on the bases, in fact, that he's been a net positive despite the total lack of a bat. He has been worth nearly 9 Wins Above Replacement for his career, or about the same as David Freese and Starlin Castro have been worth since 2013, despite a 70 OPS+.

We've maybe not told you anything you don't know yet, because of course Hamilton is fast, a great defender and can't really hit. How would that fit on a contender? And which contender?

Obviously, no team looking to win is going to trade for Hamilton looking to put his bat in the lineup every day. But that's not really the appeal here, either. You don't trade for Hamilton expecting a starter. You trade for him as a late-inning weapon to steal the biggest base possible or improve your defense at the most important time. You trade for Hamilton because for all the things he can't do, he can do things that no one else can.

What that means is that teams with weak outfield defenses, especially in big parks, who could use a defensive and baserunning boost, should be willing to take a gamble here. Again: the point here is not to install Hamilton atop the lineup every day and let him drag down the bats. It's to bring him in as needed, late in games, to make a difference. It doesn't make sense for stacked outfields with good defenders like Milwaukee or Boston, but here's who should do it. And let's also note that Hamilton's name has come up in rumors for years, and the Boston Globe's Nick Cafardo reported recently that the Indians have Hamilton "on their radar," so a trade is not out of the question.

Rockies

This is the best fit, because it's been the best fit for years, simply because the outfield in Coors Field is so massive that it demands a player with elite speed and defensive skills to cover center. Charlie Blackmon, for all of his immense contributions, isn't really that player, and the Rockies are 26th in Outs Above Average at -12. (Most of that is Blackmon, who is -8, as his once-strong speed has declined to roughly average, and he's stolen only five bases this year, after grabbing 43 in 2015.)