Diamondbacks bump struggling Melancon from closer role

When the Diamondbacks signed Mark Melancon to a two-year, $14 million contract in December, the plan was for him to nail down the back end of their bullpen.

Through the first four months of the season, that thinking hasn’t come to fruition. In 41 appearances, Melancon has a 4.66 ERA and has lost 10 games, twice his career high. Although he has converted 14 of 17 save opportunities, he’s struggled mightily in non-save situations, with a 5.57 ERA in those contests.

Now, the Diamondbacks are moving him out of his role as their closer — a spot that once felt like a formality after he made the All-Star Game and pitched to a 2.23 ERA with the Padres last year.

“We're gonna back into a situation where we don't have one closer at this point,” Diamondbacks manager Torey Lovullo said. “I had a discussion with Mark about making this move and he understood. He didn't necessarily like it, but he understood for the good of the team if it was a decision that I was making, that he was gonna support it.”

SCOREBOARD | STANDINGS | INJURIES

Lovullo added that his decisions will be matchup-based going forward.

Two of the most likely candidates to take the work are right-hander Ian Kennedy and left-hander Joe Mantiply. Kennedy’s ERA is 3.15, while Mantiply’s is 2.21. However, because Kennedy has posted reverse splits this season, both have been more effective against left-handed hitters.

Lovullo also said that Melancon will still appear in occasional save situations when the situation calls for it.

“It's just, I'm not gonna build it from the ninth inning backwards with one name,” Lovullo said.

The final straw for Melancon came in a pair of poor outings on the Diamondbacks’ recent 1-5 road trip to Atlanta and Cleveland.

On Sunday against the Braves, he entered a 0-0 game and gave up a walk-off double three batters later. The next day against the Guardians, he twice allowed the automatic runner to score in his first multi-inning appearance of the year. The first run gave him his third blown save of the year; the second gave him his 10th loss.

“I wanted to give it a couple of days,” Lovullo said of moving Melancon out of the closer’s role. “I don't think anybody in this room makes great decisions when they're emotional so I wanted to let some of the emotions settle down and I just wanted to give it a couple extra days, which I did. I wanted to have this discussion with the staff working through the off day and finalizing some thoughts today.”

On the season, Melancon’s underlying numbers back up his surface-level struggles. He’s striking out just 6.4 batters per nine innings and walking 3.2 batters per nine — both of which are significantly worse than his career numbers.

Castellanos to undergo Tommy John

Lovullo announced Friday that right-hander Humberto Castellanos will undergo Tommy John surgery. The operation will be performed by Dr. Keith Meister.

Castellanos started the season in the bullpen before moving into the rotation in mid-April. He posted a respectable 4.13 ERA over his first six starts, but allowed 11 runs in 8 2/3 innings in his final two starts.

Then, in early June, the Diamondbacks placed him on the 15-day injured list with a forearm strain. Two weeks later, they transferred him to the 60-day injured list.

Throughout June and July, Castellanos’ recovery process didn’t go as envisioned. Each time the Diamondbacks tried to ramp him up, he felt discomfort, forcing the team to re-evaluate his rehab.

“We pulled him back off of his rehab,” Lovullo said. “... We stopped his throwing program and his progression. There were some things that we were identifying that weren't allowing him to keep moving forward. So this will obviously be a setback for him, but it's something that needs to be done.”

Short hop

• Reliever Caleb Smith underwent successful surgery on his right hand. Smith broke a knuckle last week when punching “something he shouldn’t have,” according to Lovullo. Because the break was in his non-throwing hand, Smith has a chance to be back before the end of the season.

Theo Mackie covers Arizona high school sports, the Arizona Diamondbacks and Phoenix Rising FC. He can be reached by email at theo.mackie@gannett.com and on Twitter @theo_mackie.

This article originally appeared on Arizona Republic: Diamondbacks bump struggling Melancon from closer role