JUPITER, Fla. -- There may be some uncertainty about the pitching of the Miami Marlins, but there shouldn't be any uncertainty about the new pitching coach. Juan Nieves is devoted to the game, devoted to the process of teaching and devoted to the pitchers with whom he works.
In 2013, Nieves received all sorts of accolades as the pitching coach of the World Series champion Boston Red Sox. The Sox's pitching staff posted a 3.79 ERA in '13, the lowest mark for the club since '02. The 3.79 ERA was almost a full run lower than the '12 staff's ERA of 4.70. Boston pitchers set single-season franchise records in '13 in both strikeouts (1,294) and strikeouts per nine innings (8.0).
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In May 2015, Nieves was dismissed by the Red Sox, whose pitching staff struggled in part because the team no longer had an ace atop the rotation after trading Jon Lester. Nieves deserved better, but he gave absolutely no evidence of bitterness -- then or now.
"After being such a long time in the game, as a human being, personally, it doesn't define you," Nieves said. "I live for the kids. I want them to become better. I don't put a stamp on every pitcher that I've met. I've had the pleasure of knowing some great pitchers, not only on the field, but as human beings. That's what you take from it. What you take from it are the memories, and the memories of our friends and relations are what we have in life."
Nieves, a former Major League pitcher whose extremely promising career was cut short by a left shoulder injury, had put in a long coaching apprenticeship. He coached five years in the Yankees' system and nine years in the White Sox organization before serving as the White Sox bullpen coach at the Major League level for five years.

The dismissal from the Red Sox brought a benefit. It was the first summer that Nieves was home every day. He saw his children growing and succeeding and he saw his wife, Marilia, "showing values and morals to our kids. She's definitely my MVP and my CEO," Nieves said.
For the 2016 season, Nieves had an offer from another club as a Minor League pitching coordinator, but new Marlins manager Don Mattingly was looking for a pitching coach.
"We talked to Rick [Honeycutt, Mattingly's pitching coach with the Dodgers], we talked early with some other guys," Mattingly said. "Juan's name had been brought to me by a guy outside who I really trust. So when the Marlins came to me with Juan, that made it simple. Our guys on the pitching side and on the development side were all in with Juan. That made it easy for me to say, 'Hey, let's talk to him.'
"And once we talked to him, I felt very comfortable with him."
At the Marlins' Spring Training complex on Sunday, Nieves pondered the job before him. Miami has the mega-talented Jose Fernandez at the top of the rotation, but only three rotation spots are nailed down. There are also a couple of bullpen spots up for grabs and the closer's role is still open for competition.
There is a lot of inexperience here, but also a great deal of potential. Nieves approaches this job not only with enthusiasm but with affection.
"These kids have not had a lot of continuity," he said. "It takes a little time for me to know them and for them to know our structure, with Jim Benedict [Marlins vice president for pitching development] and myself.
"I think there are some very talented guys here, when it comes down to stuff. Now is how you command that stuff. Coop said it correctly," Nieves said, referring to longtime White Sox pitching coach Don Cooper. "He said: 'The first check you get is how hard you throw. Every check you get after that is where you throw it.'
"Now, it's being able to get those guys to know themselves and to teach them who they are and what their strengths are. It's a very talented group, good arms, but it's all a process. I know the players are more result-oriented, but there is a process to that.
"Rome was not built in one day. When you go to a guy, you have to have a specific plan for him. And you can't be wrong, because that's not fair to the players.
"I don't pretend to know everything, but I want to continue to learn every day and grow in that way, because it's all about the kids now."
This is not simply a coaching job for Nieves, 51, but a personal journey, a learning experience for the both the pitching coach and the pitchers.
"We're trying to piece it together for Don and for our staff and for the whole organization," Nieves said. "It's a challenge, but it's also a thrill. You get to know them on an everyday basis.
"I've seen some great arms here. Athletic guys, guys who have incredible talent. Hopefully, I'll be around long enough to see them become men and fathers. There's not a manual to that, but you can also have that relationship with them, too."