Starter Travis d'Arnaud's season ended after four games because of a torn elbow ligament and backup Kevin Plawecki isn't expected back for at least another week after breaking his left hand on April 11.
Nido was brought up when Plawecki got hurt and hit .135 with one RBI in 17 games and 37 at-bats. He was sent back to the minors after the Mets obtained Mesoraco from Cincinnati on April 8 for former ace Matt Harvey.
"This is a good opportunity for the next week-to-10 days before Plawecki comes back for him to learn a substantial amount that he's not going to learn in the next eight-to-10 days in Triple-A," Mets manager Mickey Callaway said Saturday.
Nido, 24, hit .257 with six RBI in six games at Triple-A Las Vegas of the Pacific Coast League and five at Double-A Binghamton of the Eastern League. Callaway said Nido will start Sunday.
"We have a catcher in Mesoraco that prepares the right way," Callaway said. "When you're down in Triple-A, it's really tough to simulate what you have to go through in the big leagues. We sat down with Nido today and he's going to really pay attention to what Mesoraco's doing and learn how to prepare the right way, because Nido has a very bright future in him if he does some of these things."
Lobaton was designated for assignment. The 33-year-old Lobaton hit .152 with three RBI in 18 games and 46 at-bats with the Mets this season.
"We hope Lobo stays in the organization, because he's definite depth for us," Callaway said.
New York recalled right-hander Chris Flexen and Nido from Las Vegas, and optioned left-hander Buddy Baumann to the farm team. The 23-year-old Flexen was 3-3 with a 3.40 ERA in seven starts and one relief appearances this year. Baumann, 30, is 0-1 with a 19.29 ERA in one game with San Diego and one with the Mets, who claimed him off waivers on April 27.