Lopez gave up a run on two hits in the ninth inning Monday to record his first save of the season in an 8-7 victory over Atlanta.
Lopez has posted a 2.57 ERA and 5:1 K:BB through seven Grapefruit League innings this spring.
Lopez and the Mets are in agreement on a one-year, $2 million contract, Jeff Passan of ESPN.com reports.
Lopez elected free agency Thursday after passing through waivers unclaimed, Roch Kubatko of MASNSports.com reports.
Lopez was designated for assignment Saturday, Steve Melewski of MASNSports.com reports.
The Orioles claimed Lopez off waivers from the Marlins on Saturday, Joel Sherman of the New York Post reports.
The Marlins optioned Lopez to Triple-A Jacksonville on Saturday, Jordan McPherson of the Miami Herald reports.
The Marlins acquired Lopez from the Twins in exchange for Dylan Floro on Wednesday, Craig Mish of the Miami Herald reports.
Minnesota activated Lopez (mental health) from the 15-day injured list Tuesday, Do-Hyoung Park of MLB.com reports.
The Twins transferred Lopez from the restricted list to the 15-day injured list for mental health reasons Sunday, Dan Hayes of The Athletic reports.