Valverde, who led the National League in saves in 2007 and '08, will throw another simulated game Sunday before likely beginning a Minor League rehab assignment next week.
"My legs are good and my arm is ready to pitch," Valverde said. "The thing is I haven't pitched in a month. I have to take it day-by-day and see what happens. Everything is perfect right now, and Sunday I will have to throw again and after that will go to the Minor Leagues."
Houston manager Cecil Cooper was pleased with how Valverde threw the ball and fielded his position, but his health is the main issue.
"All I'm concerned about him is the physical side, and physically, he's fine," Cooper said. "You could tell that by the way he threw the ball and moved around on the field. We're going to do this again on Sunday, and we'll make a decision after that."
Valverde said he is planning to pitch three times in the Minors, including appearances in consecutive games, before rejoining the Astros.
"I'm so excited," Valverde said. "I see my teammates excited, too, because I'm real close. I'm ready, you know what I mean? I'm ready to be in the game."
Meanwhile, reliever Geoff Geary, on the disabled list with biceps tendinitis, had his plans for a Minor League rehab assignment scrapped. Geary was originally scheduled to pitch in the first of two games for Double-A Corpus Christi on Friday, but will instead continue to rehab with his teammates.
Brian McTaggart is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.