Pursuant to the Collective Bargaining Agreement, Major League rosters expand from 26 to 28 players in September. That’s a far cry from the old 40 man September rosters.

For their September call-ups, the Mets selected infielder Deven Marrero and right-handed pitcher Adonis Medina.

Marrero, 32, began the season with the Long Island Ducks before being signet by the Mets. This will mark the second time this season Marrero was recalled.

In his last stint, Marrero was 0-for-4 over three games. In 36 games for Triple-A Syracuse, Marrero hit .217/.309/.325 with two triples, three homers, and 17 RBI.

Marrero provides infield depth with Brett Baty landing on the IL, and Luis Guillorme set to begin a rehab assignment. Previously, Terrance Gore was recalled to take Baty’s spot on the roster.

To make room for Marrero on the 40 man roster, right-handed pitcher Connor Grey for assignment.

Grey, 28, was signed as a minor league free agent by the Mets last June. He had been called-up previously this season, but he did not make an appearance. In 21 starts and one relief appearance for Triple-A Syracuse, he was 5-5 with a 5.52 ERA, 1.613 WHIP, 3.9 BB/9, and a 7.3 K/9.

Medina, 25, was purchased by the Mets from the Pittsburgh Pirates on the eve of this season. He’s been up-and-down a number of times this season.

In 13 appearances with the Mets, he is 1-0 with one save, a 4.63 ERA, 1.286 WHIP, 1.9 BB/9, and a 6.6 K/9. In 12 relief appearances and two starts with Triple-A Syracuse, he is 1-0 with a 3.71 ERA, 1.650 WHIP, 5.1 BB/9, and an 8.4 K/9.

In other important news, Michael Mayer of MMN reports the MRI on Francisco Álvarez showed some loose bodies. He will receive an injection and will return to baseball activities in 3-4 days.

Based on how Álvarez responds will determine when or if he will play again this season. Certainly, this severely reduces the chances of his getting called up the majors this season.