Could Orioles trade Jim Johnson for Porcello?

Could Orioles trade Jim Johnson for Porcello?

Published Jan. 15, 2013 10:37 a.m. ET

The Baltimore Orioles aren’t interested in trading shortstop J.J. Hardy to Detroit for starter Rick Porcello.

They may be more willing to trade closer Jim Johnson.

At first blush, that seems odd. But there’s a sabermetric rationale behind it.

Johnson could have a superb 2013 season and still not approach what he accomplished last year: He led the majors with 51 saves, made his first All-Star appearance and was one of the most dominant relievers in baseball. He turns 30 this June, so he’s right in the middle of his prime.

At the moment, Porcello is probably the best fifth starter in baseball -- considering his potential (still young at 24) and the Tigers’ pitching depth. Porcello is coming off an unspectacular season, 10-12 with a 4.59 ERA. But his numbers would improve with a better defensive infield -- which the Orioles have, with the likes of Hardy and Manny Machado.

Porcello is three seasons away from free agency, Johnson only two. Porcello has averaged a little more than 170 innings per year over his major-league career. Johnson logged just under 70 in 2012, within the normal range for a closer on a winning team.

So, Porcello figures to throw more than 500 innings before becoming a free agent. Johnson might offer only 140. Put another way: Johnson, with less than one-third of Porcello’s expected workload, would need to pitch pretty spectacularly over the next two seasons in order to be more valuable than a theoretically improved Porcello.

If Orioles general manager Dan Duquette is willing to move Johnson in the right deal, the availability of replacements would be one reason why. Free agent Rafael Soriano is unsigned, along with buy-low candidates Brian Wilson and Jose Valverde. The open market remains laden with semi-closer types like Brandon Lyon and Matt Lindstrom. Pedro Strop and Luis Ayala are internal candidates to close.

The Tigers, meanwhile, would like to add a veteran to the back end of the bullpen, in case Bruce Rondon isn’t ready to close for a World Series contender at age 22 -- without having thrown a pitch in the major leagues.