NEW YORK -- The Mets added another layer of depth to a much-improved bullpen on Tuesday, signing right-hander Jared Hughes and adding him to both their 40-man roster and 60-man player pool.

A veteran of nine seasons with the Pirates, Brewers, Reds and Phillies, Hughes posted a 4.04 ERA last year over 72 appearances split between Cincinnati and Philadelphia. He is just two years removed from his best professional season in 2018, when he produced a 1.94 ERA and held opposing hitters to a .212 average over 78 2/3 innings.

According to a source, Hughes will receive $700,000 pro-rated for 2020, which equates to about $260,000 over a 60-game season.

Hughes is also the only Major League pitcher to appear in at least 63 games in each of the last six seasons; his 417 appearances over that span rank third in MLB behind only Bryan Shaw (439) and Tony Watson (428).

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Hughes spent most of Spring Training in Astros camp, where he allowed four runs in five appearances. When the Astros declined to commit a 40-man roster spot to him in mid-March, Hughes used the out in his contract as leverage to have the team release him.

Because Hughes, 34, is now on a Major League deal with the Mets, he is more likely to make the Opening Day bullpen over other, less established relievers. The Mets will enter Summer Camp with a crowded bullpen, which includes Edwin Díaz, Seth Lugo, Dellin Betances, Jeurys Familia, Justin Wilson, Robert Gsellman, Brad Brach and Hughes. Given that Opening Day rosters will feature 30 players rather than 26, the Mets can carry additional relievers on top of those eight, but that octet will form the core of the bullpen.

The signing of Hughes marked the latest in a flurry of transactions this week for the Mets, who also inked veterans Melky Cabrera, Gordon Beckham and Hunter Strickland to Minor League deals, while also re-signing Ryan Cordell and Erasmo Ramirez. Their 60-man roster pool now stands at 51 players, with room to add up to nine more over the rest of this week.