The Mets rounded out the back end of their bullpen Wednesday night when they agreed to terms with veteran reliever Antonio Bastardo. The lefty signed a two-year, $12-million deal, a source confirmed.

It’s hardly the blockbuster reunion with Yoenis Cespedes that fans have been holding out hope for this offseason. Nevertheless, the addition of Bastardo gives the Mets a much steadier bridge to closer Jeurys Familia.

advertisement | advertise on newsday

Bastardo, 30, posted a 2.98 ERA in 66 appearances for the Pirates last season. Despite battling command issues throughout his career, Bastardo has turned himself into a strong setup option.

It’s exactly what the Mets had been seeking this offseason with the departure of Tyler Clippard via free agency. Bastardo will slot into the back end of the bullpen, alongside Familia and righthander Addison Reed, who gives the Mets another option in the eighth inning.

Bastardo also gives the Mets an added weapon against tough lefthanders, joining lefty specialist Jerry Blevins. Though Bastardo is accustomed to facing both righties and lefties, he’s been particularly successful against lefthanders, holding them to a .178 average.

Bastardo’s signing checks off one more of the Mets’ offseason goals. They still seek a righthanded bat for the outfield.

advertisement | advertise on newsday

Cespedes, of course, would theoretically fit that bill. But with the Mets still unlikely to meet the slugger’s asking price, they will almost certainly aim for a less costly option.