– For all the joy that commanding a playoff team brought Paul Molitor last season, there was plenty of angst, too, much of it supplied by his bullpen. The Twins manager is reminded of that every time he looks in a mirror and sees those gray hairs curling around his temples.

“I lost a lot of ground in that fight last year,” Molitor joked Thursday after watching the Twins’ second workout of training camp. “I try not to pull out that picture from three years ago too often, because it’s changed.”

There’s good news for Molitor, though: His bullpen has changed, too. And the most noticeable upgrade is the presence of a trio of pitchers who have more than a few gray hairs of their own.

The Twins’ major free-agent acquisitions this winter were all relief pitchers, intended to buttress a bullpen that had a 4.40 ERA last year, 12th out of the 15 AL teams, and struck out fewer batters per inning than all but one other MLB team. New closer Fernando Rodney, potential setup man Addison Reed and lefthander Zach Duke were brought on board to get critical outs, but also to help some of their young teammates better learn how.

“Those guys have the experience and ability in how they pitch, but also they know they have a chance to help out our guys,” Molitor said. “We lost a couple of guys who served in those roles last year [in closers Brandon Kintzler and Matt Belisle], and I think some of these [new] guys are going to step into that eventually, too.”

Duke, born on the same day as new teammate Joe Mauer — April 19, 1983 — is ready to give it a try, even if he sounds a little amazed that he is nearly 35 already.

“I suppose I’m a veteran, right?” the 13-year major leaguer and 2009 All-Star said with a laugh. “Guess so — I’m second oldest [in the bullpen, behind Rodney, soon to be 41]. Fernando’s got a ton of experience, and I do, too. It’s going to be such a good mix, to have guys who have been there and done it in high-level situations. It comes down to having open-minded communication between us older guys and the younger ones.”

Duke has a lot to teach, though. As a pitcher whose first six seasons were spent as a starter, he can help Tyler Duffey with the adjustment to bullpen life. As a lefthander who takes pride in being more than a lefty specialist — since switching to the bullpen full-time, he has held righthanders to a .238 average from the sixth inning on, with only six homers allowed and 106 strikeouts in 370 plate appearances — he might help fellow lefty Taylor Rogers iron out his own platoon split.

And as someone who holds the unofficial major league record for recovery after Tommy John surgery — he was on the mound in mid-July last year, following the elbow ligament transplant operation the previous October — he figures to be a good resource for Trevor May’s comeback.

“I’ll certainly try to share some secrets of what I did. I don’t know that it should be anyone’s goal to make it back as fast as I did, but I’d certainly like to help guys get through the process without having setbacks,” Duke said. “Little injuries crop up, and I had some pretty good information that was given to me, some little secrets, I guess, that really helped with that.”

Duke’s recovery is particularly remarkable considering the damage he had done while enjoying a terrific 2016 season with the White Sox and Cardinals. He posted a 2.36 ERA, but an exam after the season uncovered lots to fix.

“In addition to the Tommy John, I tore a flexor tendon off the bone,” Duke said. “[Surgeon Dr. James Andrews] shaved a bone spur off the back of my elbow. A couple of loose bodies came out.

“I had a lot going on in there. I’ve still got the bone chips in a jar.”

And after a quick comeback in 2017 in order to re-establish some value and attract free-agent suitors, he has found a new home.

“The elbow feels great. We’ll see how my arm responds, but there haven’t been any problems since I got back,” Duke said. He met with Molitor on Thursday morning “and told him I like the ball in big situations. I’m willing to take it whenever they decide they want me to have it. We have a lot of capable guys in this bullpen, which is a good thing.”