"Thank God it was nothing serious," Zambrano said of the test results.
If he feels up to it, Zambrano will play catch either Sunday or Monday, and could be ready to start next weekend at Houston.
"The results were good," Cubs manager Lou Piniella said. "We want to make sure that this guy is OK. If it's 'iffy,' we're not going to take a chance."
Zambrano was examined by team orthopedic specialist Stephen Gryzlo on Wednesday, but did not take an MRI exam. Why? Apparently, he had a full schedule, which included taking his wife, Ismary, to the hospital for surgery. She's fine now, Zambrano said.
As he explained it, Zambrano woke at 6 a.m. CT on Wednesday to take his wife, then had breakfast, got a haircut, bought some medicine, went back to the hospital to see his wife, then to Chicago to see Gryzlo.
"They said I had to do the same thing I did back in June when I did the arthrogram," Zambrano said of his doctor's visit. "I didn't do the MRI [arthrogram] because I didn't want to miss three starts, because I knew I was feeling better. I knew if they put that shot in my arm, I'd have to miss two, three starts like last time. I said I didn't want to do the arthrogram, I just wanted to do the plain MRI. They were OK with that. I went the next day [Thursday for the MRI]."
In June, Zambrano had inflammation in his shoulder, underwent an MRI arthrogram and was placed on the 15-day disabled list to give him time to heal. This time, there's no pain in his shoulder. Back to Wednesday: After seeing Gryzlo, Zambrano met with Cubs general manager Jim Hendry at Wrigley Field.
"[Hendry] told me, 'Take the rest of the day off and be with your wife,' and that was my day," Zambrano said. "I'm still stressed from that day but I'm here."
Last Tuesday against Houston, Zambrano came out of the game after five innings because of the discomfort in his shoulder that got worse as the game went on.
"I don't want to put this team in some situation where they lose me," Zambrano said. "You can be a hero, but you have to be smart, too."
When he was sidelined in June, the feeling was that Zambrano would be fresher down the stretch.
"I think it's like I said the other day -- I've been throwing 200 innings," Zambrano said. "It's the first time in my career I've felt this. I promise the team, and I promise the Cubs fans I will work hard in the offseason and the rest of this season to keep my shoulder strong. There's nothing to worry about."
Was he angry at the media reports about him skipping the MRI?
"No, it was funny," Zambrano said. "My wife woke up and she was reading the paper. She told me they were saying this in the paper and saying that. I said, 'Really?' I have seven, eight years in the big leagues. I know how to deal with that."
Can he still hit?
"Right-handed, yes," he said.
Carrie Muskat is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.