The Yankees’ bullpen depth hurts their trading prospects

We’re in the thick of trade season, and not a day goes by without a rumor, a whisper, or a full-length post about another player the Yankees have kicked tires on. With the obvious need for pitching, New York’s been tied to Madison Bumgarner, Marcus Stroman and others. As has been their MO for the past number of years, the Yankees have also been linked to the top available relievers like Ken Giles and Shane Greene.

Relievers have become the most sought-after commodity come trade deadlines, and in fact, the Yankees were one of the catalysts of this trend when they traded Aroldis Chapman and Andrew Miller for a king’s ransom back in 2016. The logic behind the Reliever Premium is pretty straightforward; you can leverage relief pitching in the playoffs more than you can any other player group.

A position player plays pretty much every game in the regular season and pretty much every game in the postseason. A starter is held to a firm schedule in the regular season, and can sometimes be leveraged to pitch more often in the postseason, but there’s still a highly defined regimen. Relievers can pitch a whole lot more in the postseason, with more off days and every inning a high-leverage one, so you get more value “per pitch”, or per appearance, than the other two groups.

In 2016, Miller appeared in 10 of Cleveland’s 15 postseason games, throwing 19.1 innings. That same year, Chapman worked 13 of 17 Cubs playoff games, for 15.2 innings. Just last season, Josh Hader threw 10 innings over seven games for the Brewers, only resting for three of Milwaukee’s postseason dates. This shows how teams can leverage relievers like no other players in the postseason.

This ability to get creative with relief pitchers, however, might actually work against the Yankees. Their bullpen is already so deep that it’s hard to find ways to achieve greater leverage with a new reliever. If Ken Giles ends up in Minnesota, Atlanta or Houston, he becomes one of the top three options in their bullpen. If he comes to the Bronx, he’d be one of five or six options, roughly on par with Chapman, Zack Britton, Chad Green, Adam Ottavino and Tommy Kahnle.

On one hand, this is truly quite something. The Yankees could just trade for Giles or Greene and roll out an even more ludicrous relief corps, everyone working one inning and combining to strike out somewhere around a dozen batters. The diversity of options, however, means a new reliever can’t be leveraged the same way, which introduces a question of value to the Yankees.

The ability to leverage an acquired reliever makes him more valuable to a buying team, so they’re going to be willing to pay more. A team like the Twins, Braves or Astros can be more creative and ask more of a prospective reliever than the Yankees can, because the latter team just has so many other options that will all be used in a postseason run. As such, the Twins, Braves or Astros are likely to be willing to pay more than the Yankees, and trade talks are effectively an open auction: all participants make public bids and the highest bid wins.

This doesn’t really matter in discussions around starting pitching, since the potential for creative use is a lot lower, and the Yankees could easily slot a higher-performing starter into CC Sabathia or J.A. Happ’s spot. On the relief front, the Yankees’ indomitable existing bullpen might introduce a structural obstacle to trades, and perhaps further emphasizes that Brian Cashman’s focus should be on the rotation as July 31 approaches.