Gene Roof was a Triple-A outfielder in his late 20s in 1986 when new Tigers player development director Joe McDonald approached him with an offer. His playing days were numbered, but McDonald was interested in making Roof a coach for their Triple-A club in Toledo.

One problem: Longtime Tigers general manager Jim Campbell wouldn’t approve money for another Minor League coach. So McDonald proposed signing Roof as a player.

The 29-year-old Roof had five at-bats over five games in his final season as a player. He never imagined that would be the springboard for 33 more years in the Tigers' organization.

“If it weren't for Joe McDonald, I wouldn't have a job,” Roof said Friday.

That tenure ended this fall with Roof’s retirement.

“We’ve been fortunate to have had Gene Roof with our organization for close to over three decades, and personally, I’ve appreciated and enjoyed working with him for 19 years,” Tigers general manager Al Avila said in a statement. “Gene comes from a wonderful baseball family who have dedicated their lives to coaching and teaching players. Gene’s commitment at both the Major and Minor League level is a testament to his passion for the game, and he has positively impacted the development of countless Tigers players. I can tell you from ownership on down, we appreciated his devotion to making our players better. We wish he and his wife, Marianne, nothing but the best in retirement, and look forward to honoring his career with the Tigers prior to a game at Comerica Park during the 2021 season.”

The impact Roof made across the Tigers' system with players past and present -- and outfielders from Bubba Trammell to Curtis Granderson to Nick Castellanos to Riley Greene -- will be felt for a long time. More than a baseball lifer, Roof has been a tremendous teacher.

“Those guys, you don't forget how hard they worked,” Roof said. “And then, the smile on a player’s face when you tell them they’re going to the big leagues to chase their dream.”

That last part was Roof’s job as Toledo manager from 1997-99. He managed up and down the Tigers' farm system, from Class A Fayetteville (1989-90) to Double-A London (1991) and later Double-A Jacksonville (2000). Among the future Tigers he managed were Gabe Kapler, Frank Catalanotto, Robert Fick, Matt Anderson and Brandon Inge.

“Managing Brandon Inge, that was a classic for me, the way he went about his business, the way he played,” Roof said.

Roof also had a four-year stint as the Tigers' first-base coach under then-manager Sparky Anderson. But for the past 20 years, Roof has used his role as Minor League outfield instructor to help turn prospects into Major Leaguers.

Among Roof’s students:

• Curtis Granderson: The Tigers drafted him in the third round in 2002. He spent the next three-plus seasons climbing the developmental ladder before becoming an All-Star in Detroit.

“The way he went about his business, every day he came to the ballpark with a smile on his face but a determination to be better,” Roof said.

• Don Kelly: Detroit drafted him as a shortstop, and he came up through the system as an infielder. But he eventually stuck in the big leagues as a superutility player, including the outfield.

“Don Kelly was a great student,” Roof said. “He was probably the easiest.”

• Nick Castellanos: The former first-round pick converted to outfielder in 2013 before third base opened for him. A few years later, Castellanos became an outfielder again.

“The amazing thing about Nick, he never complained about doing extra work,” Roof said. “Every day after the game, he'd come and ask, 'what are we doing tomorrow,' even on the road. To me, that was great working with him.”

• Dave Roberts: Roof worked with the Tigers' Draft pick as an outfielder at Class A Visalia in 1996.

“It's kinda cool that you work with them and then they go to the big leagues as a player and then as a coach,” said Roof.

• Christin Stewart: Among Roof’s drills with the former first-round pick was to have Stewart try to throw from the outfield with his eyes closed so he could learn to trust his mechanics.

“Christin Stewart was somebody we really had to work hard, but he really worked,” Roof said, “and now he's a respectable big league outfielder.”

Roof's last set of pupils included Greene, Parker Meadows and Daz Cameron, all at the alternate training site in Toledo. He sees a bright future ahead.

“I think Riley Greene is going to be a very special player,” Roof said. “I think Parker Meadows really grew up [this summer in Toledo]. He's going to come a little slower than Riley Greene, but he has all the tools to be a really special player.”

Roof will be following from afar. He still loves his job, but he decided this summer that he wanted to be home with his wife. His coaching legacy will continue with his kids. Oldest son Shawn is a manager in the D-backs' system. Middle son Eric is the head coach at Eastern Michigan University; youngest son Jonathan is an assistant there. Daughter Jacqueline was a three-time All-American in softball and just took a coaching job.

Not bad for an old Mud Hens outfielder.

“It was pretty tough to walk away, take the uniform off,” he said. “But when I made my decision, I'm comfortable with it.”