This story was excerpted from Bryan Hoch’s Yankees Beat newsletter. To read the full newsletter, click here. And subscribe to get it regularly in your inbox.

Growing up about 10 miles outside Pittsburgh, Sean Casey dreamed of becoming a left-handed-hitting Major League first baseman. He also dreamed of doing that in Yankee pinstripes.

“You know what’s funny?” he asked in his gravelly, always enthusiastic voice. “I had a poster of Don Mattingly up on my wall at home until like 10 years ago. It was a Sports Illustrated poster of him coming out of the box. I just loved the man.

“It was the time I just started collecting baseball cards in the ’80s -- I think Mattingly’s ’84 Donruss was a big deal. I just loved the left-handed-hitting first baseman.”

Casey not only became a left-handed-hitting first baseman in the big leagues, but he thrived in the role -- particularly at the plate. From 1997-2008, he hit .302/.367/.447 and spent most of his career with the Reds (1998-2005).

While he never got to don a Yankees uniform as a player, Casey is in one now as the club’s new hitting coach. With New York’s lineup struggling without its injured anchor, Aaron Judge, the hope is Casey’s infectious energy will find its way into Yankee bats like the way electricity seemed to emanate from Mattingly’s lumber in the mid-1980s.

Upon learning that he’d be a Yankee, Casey did something symbolic that he’d never done before to show his appreciation for “Donnie Baseball.”

He grew a mustache.

“I never had a mustache in my life -- always a goatee,” Casey said. “Then one day, I was gonna shave the goatee, and I thought, ‘You know what? I’ve always wanted to be like Don Mattingly, might as well keep the ’stache.’”

The Mattingly mustache was a signature look, an unmistakable marker of the era if you were a baseball fan in the 1980s, when he was among the game’s elite hitters and on a Hall of Fame track before back injuries derailed him.

So, what does the “Hit Man” think of Casey’s tribute?

“Looking good,” Mattingly said. “A tint of gray in there. Mine is Santa Claus white at this point.”

“Santa Claus white” is definitely not the color the Yankees want to see Casey’s mustache become while he tries to right what has gone wrong with New York’s lineup.

But Casey is confident the names on that lineup card each day are too good to continue in the current doldrums.

“At the end of the day, they have a lot of great players here,” Casey said. “I come with my pedigree or my resume, and I’m really excited to be here and connect with these guys.

“But there’s too much talent here not to get going.”

MLB.com’s Manny Randhawa contributed to this newsletter item.