Satin, a 28-year-old corner infielder who's only had a couple cups of coffee in the big leagues, has hit .306/.421/.491 for Triple-A Las Vegas. Even in the hitter-friendly Pacific Coast League, that's not a bad triple-slash line. In addition, he's been particularly excellent against left-handed pitchers, hitting .344/.475/.516 against them.
Josh Edgin started the years with the Mets after working his way up to the roster in the second half of last season. He struggled early in the year before getting demoted to Double-A Binghamton and then promoted to Triple-A Vegas, but his 9.64 ERA in the big leagues was more than double his 3.60 FIP. The same has been true in his stint in the minors, but he's likely going to be an improvement over Carson.
Cowgill, too, started the year with the Mets, but he barely hit after belting a pair of home runs early in the season. He's put up a .799 OPS in 139 plate appearances in Vegas since his demotion.
In terms of roster management, Edgin clearly replaces Carson as the bullpen's second lefty. Satin takes Davis's spot, though it wouldn't be surprising to see the Mets toy with different combinations of Satin, Justin Turner, Daniel Murphy, and possibly Jordany Valdespin on the right side on the infield, depending on platoon situations. With Cowgill on the roster, the team will still carry six outfielders, an odd choice.