"I have such fond memories," Mills said of Houston. "I love the city and love the people here. A lot of friends. It was just real different, riding in from the airport and coming out to the ballpark."
Mills arrived at the ballpark early Friday, taking a walk down memory lane, visiting with old friends.
He had been in the visiting clubhouse at Minute Maid Park in 2008 when he was a coach for Terry Francona with the Red Sox. This time there were stronger ties to the team in the home clubhouse.
"You spend almost three years with a lot of those players out there," he said. "Your heart is with those guys, because every day for six, seven months you're with them. It's weird. All of a sudden you're not with them anymore. It's kind of fun to come back and see them."
The Astros are in the middle of a total rebuilding process, but Mills does keep an eye on several of his former players.
"Do I follow the box scores?" Mills said. "No. But when you watch the MLB channel and watch the highlights to see how they're doing, there's no doubt [I root for them]."
Mills does not allow himself to take pride in the individual accomplishments of his former Astros.
"Pride is a strong word," he said. "You know how hard these guys have worked to improve and get better. You smile and say, 'Nice going.' You're happy to see them make progress."
Mills remained a man without ego or bitterness on his return. He was fired by the Astros on Aug. 18, 2012.
"You try to do the best you can, try to help these guys get better," he said. "I think that was our goal every day. I think we did that. You see these guys and you watch the progress, the scouting videos, and you see some of these guys doing well, you're rooting for them individually because you spent so much time with them.
"This being my first [managerial] job, you might look at it a little different. You learn and improve all the time. Would you do some things different? I would do a couple of things different. You hope you get better. This game is constantly changing.
"Being cynical doesn't help anybody. For 30 minutes after that Saturday night in August, maybe I was [cynical]. Then I realized that's not healthy to me at all. Or anyone else. That's over with, and let's move on."
Mills claimed he didn't give the Cleveland pitchers any advice on how to pitch to the Astros this weekend.
"Our advance staff does such a good job, I think I would only confuse them," he said. "The last thing I want to do is get in the way."
Mills did say that he helped the Indians' outfielders on how to play the bounces off the walls at Minute Maid Park, particularly off the scoreboard in left field and Tal's Hill in center.
Mills spent Saturday morning with his son Beau at a ranch in Orange, Texas, about 80 miles east of Houston, where Beau raises and trains bucking bulls.
"When I was a young kid in junior high school, I used to ride steers," Mills said. "No. 1, I wasn't very good at it, and No. 2, it took time away from baseball. And I didn't want to get hurt, because I enjoyed baseball so much, so I dropped it."
Mills admitted he doesn't miss the daily manager press conferences with the media.
"There's been more than one day when Terry goes out for his press conference and I say, 'Better you than me,'" laughed Mills.