Melancon, 31, put together another solid season for the Pirates, leaving the club with 30 saves, a 1.51 ERA, and a 38/9 K/BB ratio in 41 2/3 innings. He led the majors last season with 51 saves and has a 1.80 ERA since joining the Pirates in 2013. Melancon is earning $9.65 million this season and can become eligible for free agency after the season.
With Melancon out of the picture, the Pirates intend to have Tony Watson take over the closer’s role.
Rivero, 25, has handled the seventh and eighth innings for the Nationals this season, compiling a 4.53 ERA and a 53/15 K/BB ratio in 49 2/3 innings. He’s just shy of one year of service time, so the Pirates will have control of him for a long time.
Hearn, 21, was rated the Nationals’ 27th-best prospect by MLB Pipeline. He was originally drafted by the Pirates in the 22nd round of the 2012 draft but he didn’t sign and ended up going back to college. The Nationals took him in the fifth round of last year’s draft. This season, between rookie ball and Single-A Hagerstown, Hearn put up a 2.79 ERA and a 39/13 K/BB ratio in 29 innings. He’s a long way away from the majors, so he’s essentially a lottery ticket for the Pirates.
The Nationals needed an upgrade at closer as Jonathan Papelbon has struggled this season. The right-hander has allowed runs in each of his last three appearances, ballooning his ERA up to 4.41 with a 30/13 K/BB ratio in 32 2/3 innings. It will be interesting to see how Papelbon, who has never made a habit of letting his feelings go unspoken, handles a demotion to the eighth inning.