NEW YORK -- The New York Mets have surged into the second National League wild-card spot by posting the best record in the majors since June 1. Their bullpen, however, remains a glaring weakness, and the need for upgrades with Tuesday's trade deadline looming only grew with a series of moves ahead of Kodai Senga's season debut Friday night against the Atlanta Braves.

Dedniel Núñez, an out-of-nowhere pillar for the Mets' relief corps, was placed on the injured list with a right pronator strain. Meanwhile, veteran reliever Shintaro Fujinami, who was expected to bolster the bullpen when he signed for $3.35 million during the offseason, was designated for assignment before ever throwing a pitch for the club.

The team also officially reinstated Senga from the 60-day injured list, recalled right-hander Eric Orze from Triple-A Syracuse, and designated right-hander Adrian Houser for assignment.

Fujinami, 30, was expected to make the Mets' roster out of spring training, but his command struggles in camp were so severe that the Mets sent him to Triple-A to begin the season to correct the issue. But bouts of wildness continued. He was placed on the injured list in early May before starting a rehab assignment in late June. The 30-day rehab clock expired this week. The Mets could have optioned him to the minors again but instead chose to DFA him.

The 6-foot-6 right-hander posted a 10.95 ERA over 14 outings for Syracuse. He issued 25 walks in just 12 innings.

While Fujinami failed to deliver, Núñez, a 28-year-old rookie, emerged as a crucial piece in the Mets' bullpen. Núñez began the season in Syracuse. He was called up for one outing in early April, sent down again, called up a second time for three outings, and demoted again before sticking in late May.

The right-hander has recorded a 2.43 ERA with 45 strikeouts to eight walks in 33 innings for the Mets this season.

Orze, 26, returns to the Mets after making his major league debut on July 8 and being sent back down to Triple-A two days later. Houser, a 31-year-old right-hander, pitched to a 5.84 ERA in 23 appearances, including seven starts.