Lyon, who hasn't faced batters or appeared in a game this spring after having a cyst drained in his right shoulder, threw 30 pitches off a bullpen mound Monday afternoon. It was the second time in three days he tossed 30 pitches from the mound.
"We'll see how my arm reacts again [Tuesday], but everything went well and the ball was coming out of my arm pretty good," Lyon said. "I'm comfortable where I'm at right now. We'll just come in [Tuesday] and see how it feels and kind of work from there. I don't know when I'm going to get on the mound again, but if I feel good maybe do a light thing [Tuesday]."
Lyon could possibly face hitters by the weekend. Houston manager Brad Mills said Monday he's not yet worried about Lyon not being ready for the start of the regular season.
"We still have plenty of time," Mills said. "Those concerns still aren't going to come for another week. If he stops progressing like he has, those concerns might come up a little bit, but it's not at that point yet."
Lyon remains confident he'll be ready by the end of the month.
"They always say Spring Training is for the starters and their pitch counts," he said. "As a reliever, we have the luxury of not having to throw so many pitches in Spring Training. Obviously, you'd like to get your full work in for six weeks, but I'm confident that if everything keeps going the way it's going I'll be ready go to."
Lyon is keeping his bullpen sessions to 30 pitches at varying intensity.
"Every day your arm feels different and you can't throw as hard as you want, and you have to take it easy to keep it loose and strong," he said.
Lyon, who signed a three-year, $15-million contact in December, could be Houston's closer this year. He went 6-5 with a 2.86 ERA in 65 games last year with Detroit, and saved 26 games for Arizona in 2008.
Brian McTaggart is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.