"So obviously he feels good enough to finish up this week and call the game, so we're very, very excited for that and to have him back and keep him involved," Fisher said. "We're praying for him, and it's been a very, very emotional day, but it's been great to get him back. Guys were happy to see him this morning."
Heimerdinger isn't talking with reporters this week. He walked out to practice and went to work. Cornerback Cortland Finnegan ran by and patted the coordinator on the back at one point.
"It means a lot for him to come out here," Finnegan said. "Dealing with what he's dealing with, it speaks volumes the kind of man he is."
Fisher said football is Heimerdinger's love and passion. Focusing on his job offers a break for Heimerdinger before starting treatment.
"He understands now what's ahead," Fisher said of his coordinator and friend. "He's got a tremendous fight ahead of him. At least he knows what to prepare for and when to prepare for it, so that speaks volumes of his commitment to this organization."
The Titans (5-5) are very happy to see Heimerdinger well enough to return for another reason. Rookie quarterback Rusty Smith will make his first NFL start against the Texans (4-6), and Fisher was preparing for quarterbacks coach to handle play-calling Sunday, with help from himself and offensive line coach Mike Munchak.
Kubiak said after practice Thursday that he spoke with Heimerdinger on Wednesday.
"You just pray for him that hopefully some positive things happen along the way, but he was very upbeat," Kubiak said. "I got a chance to visit with his son yesterday before I got him on a plane and flew him to Tennessee. I just wish Mike the best and say a lot of prayers for him. He's a great person. It's very tough, but Mike's a tough guy, too."
"Dinger saw me throwing up in the sink, and he knew something was wrong," Shanahan said, according to The Washington Post. "... He saved my life."
The Associated Press contributed to this report.