White Sox to sign reliever Kelvin Herrera, outfielder Jon Jay

The White Sox added proven relief help to the back end of their bullpen Monday, agreeing to terms with right-hander Kelvin Herrera on a two-year, $18 million deal, with a vesting option for a third season, a source confirmed.

A two-time All-Star, Herrera posted a 2.44 ERA in 44 games between the Royals and Nationals last season. He closed for the Royals, was traded for three minor leaguers including the Nationals’ 11th- and 12th-ranked prospects, and was used mostly as a set-up man for the Nats before his season was halted by a Lisfranc ligament tear in his left foot on Aug. 26. He also dealt with a rotator cuff impingement last season and forearm issues in 2017.

Herrera, who turned 29 on New Year’s Eve, saw his velocity, strikeout and ground ball rates drop last season while he recorded 17 saves, but the Sox are confident he will be healthy. Herrera owns a 2.82 ERA with 60 saves in eight seasons.

The Sox also reached an agreement with outfielder Jon Jay, according to reports. Jay, 33, is a good friend of free agent Manny Machado, a much bigger free agent prize being pursued by the Sox, who traded for Machado’s brother in law, Yonder Alonso, last month.

The Sox bullpen is shaping up. They traded catcher Omar Narvaez to the Mariners last month for right-hander Alex Colome, a 2016 All-Star who notched 47 saves in 2017 with the Rays, and also picked up Nate Jones’ $4.65 million option for 2019. Colome, Herrera and Jones are all capable of handling the eighth and ninth innings.

Other bullpen possibilities exist in the Sox’ young contingent of arms including lefties Jace Fry, Aaron Bummer and Caleb Frare and righties Ian Hamilton, Ryan Burr, Juan Minaya and Zack Burdi, a 2016 first-round draft pick ready to return from Tommy John Surgery.

Even if they don’t sign a top free agent such as Machado or Bryce Harper, an improved bullpen should help the Sox avoid another 100-loss season, especially in a AL Central that looks like one of the weaker divisions in baseball. If the Sox are out of contention near the trade deadline, they’ll have the flexibility to trade Herrera to a contender for more prospects.

In any event, while still focusing on a long-term plan in the third year of their rebuild, the Sox have had their fill of tanking and potentially could turn a corner by adding prized prospect Eloy Jimenez to the roster as well as off-season acquisitions Herrera, Colome, right-handed starter Ivan Nova, first baseman Alonso and catcher James McCann.

Meanwhile, the Sox remain in the hunt for Machado and Harper with their chances for the former seemingly better than the latter in a free agent derby that might not reach a conclusion for weeks.

Herrera’s deal, first reported by ESPN, has not been announced. The Sox’ interest in Jay was first reported by Ken Rosenthal of The Athletic.