"He told me it was official, that he was retiring," Roethlisberger said. "He thanked me for being his teammate and said how lucky he was to play with just one quarterback for all of his 11 years in the NFL. I told him he had it all wrong. I told (him) I was the lucky one."
The Steelers' star quarterback pointed to Miller's unselfishness when explaining why he sees him as the greatest teammate he's been around.
"No doubt he was," Roethlisberger said. "I've had a lot of great teammates, a lot of guys I could put up there. But what Heath personified as a player and a teammate? There’s never been another like him. I've never known a more unselfish player.
"I'd ask him if he was open on a play and he would say 'no.' Other receivers say they are open on every play, but he never did. Then, I would look at the film and he'd be wide open. He always told me he didn't want me to have to worry about him."
Miller missed just eight games after joining Pittsburgh as a first-round pick in the 2005 draft, growing alongside Roethlisberger - a first-round pick in 2004 - and eventually becoming the franchise's top tight end in all major receiving categories.
From both a leadership and production standpoint, the Steelers will now have a significant void to fill as they look to capitalize on their potential for another Super Bowl run.