Lyon was placed on the 15-day disabled list May 5 with biceps tendinitis and a partial tear of his right rotator cuff after blowing his fourth save of the season. In 12 games this year, he's allowed 21 hits and 22 earned runs in 11 1/3 innings.
"I'm doing OK," Lyon said. "I'm able to functionally move my arm, and I haven't been able to do that in the last couple of weeks. Just getting a cortisone shot helps me stretch it out a little bit, and it feels a lot looser. It doesn't feel as tight and feels like I have built up some strength.
"It's going to take time, and when I feel like it's time for me to start throwing and I'm strong enough to start throwing, that will be the time. We haven't put a time frame on it. Even in the last couple of days when I haven't thrown, I can totally tell a difference."
Lyon, who converted 20 of 22 save chances last year, is confident he can return to form by taking a non-surgical route to heal the shoulder.
"I'm ready confident, especially after talking to the doctors and knowing how weak my shoulder was after testing its strength," he said. "I feel like if I can get my strength back, that's going to help us out a lot. I feel like I've been throwing with a weak shoulder for a little while and wasn't getting the results I needed to get and wasn't getting better. I felt it was time to back it down and get my shoulder stronger for the rest of the season."