Dominic Leone gave up three runs in the sixth in his D-backs debut and the Mets added three more runs in the eighth and ninth.
"It's just tough, you know, [Leone's] just trying to impress his teammates and impress his new fans and probably trying a little too hard," D-backs manager Chip Hale said. "He'll get it. He's got a good arm."
Leone was acquired by the D-backs on Wednesday in the trade that sent Mark Trumbo and Vidal Nuno to the Mariners for a four-player package. He gave up a two-run double to Kevin Plawecki that hit off the center-field wall and put the Mets ahead 2-1. Two batters later, Ruben Tejada added a run with a sacrifice fly.
"Everything was up," Leone said. "They put some good swings on some balls that they should've hit, and they did. They just made the best of the mistakes that I made."
In 10 relief appearances with the Mariners, Leone was 0-4 with a 6.35 ERA. Last season, the right-hander was 8-2 with a 2.17 ERA in 57 appearances.
Addison Reed had pitched well in his last few outings as he continued to work out the mechanical issues that cost him the closer's role in May. He had made five straight scoreless appearances spanning 5 2/3 innings before allowing a run in an inning on Thursday.
Curtis Granderson hit a pinch-hit RBI single off Reed to make it 4-2 in the eighth. Then in the ninth, D-backs reliever Daniel Hudson gave up a two-run homer to John Mayberry Jr.
Before the bullpen's struggles, Ray threw five scoreless innings. In both the first and second innings, the left-hander allowed a runner to reach third with no outs. But each time, Ray retired three straight Mets to prevent a run from scoring and strand a pair of runners.
Ray was called up from Triple-A Reno to start after Archie Bradleywas placed on the 15-day disabled list earlier in the day. He has now allowed just one run over 11 innings in two starts for the D-backs this season.
However, Arizona hasn't had a starter complete six innings in any of its last five games.
"Just a couple times I wasn't able to put away hitters and got deep in the counts," Ray said. "A couple times tonight I went 0-2, 1-2, and guys are battling. I'm just going to work on in my next bullpen just being able to put guys away."