Guerrero suffered the injury while throwing a low, left cross against a sparring partner during training Wednesday evening in Big Bear, Calif. The injury forced the cancellation of Guerrero's fight against Marcos Maidana, which was to be televised on HBO on Aug. 27.
"Todays' MRI results revealed a partial tear of a tendon Robert's shoulder in the rotator cuff, but they're going to meet on Monday with [San Francisco 49ers team physician Michael] Dillingham to get an official prognosis," said Santos.
"X-rays yesterday showed that there were no broken bones or anything, and in the opinion of [Dillingham's] assistant doctor, who checked out Robert today, there is nothing with the injury that is career-threatening. So that's positive big news. It showed no tearing in the labrum, and that was what we were really concerned with."
Guerrero has dealt with other setbacks during what has been an inspirational but sometimes-difficult career. Guerrero chose in March of last year to pull out of a scheduled clash with Michael Katsidis in order to be with wife Casey during her recovery from a bone marrow transplant.
Guerrero's devotion to his wife was recognized by his receiving The Bill Crawford Award for Courage In The Face of Adversity from the Boxing Writers Association of America in May.
"My family has been through the trenches with cancer. If you have faith in God, you can get through anything," said Guerrero, who returned to the ring with a eighth-round knockout of David Arrietta last April after being assured that Casey's cancer was in remission.
"This right here doesn't even scratch the surface. You've got to humble yourself. It's like God's saying, 'don't worry, son, when the time is right, you're going to just explode.'"
In this Q&A, Guerrero spoke to RingTV.com about his injury, Maidana and recent comments by Amir Khan, the WBA and IBF beltholder.
Khan initially implied on his Twitter account that Guerrero faked the injury to get out of facing the hard-punching Maidana, loser of a unanimous decision to Khan in December. Khan later apologized for the remarks.
RingTV.com: What are your thoughts on your situation, do you feel down?
There's some damage in there according to Dr. Dillingham's assistant, but I'll find out more on Monday. Once I talk to him, then I'll find the solution to getting everything fixed so that I can get back into the ring and then I can start rocking and rolling again.
RingTV.com: What led to the injury during sparring?
RG: I was in there sparring and I went to throw a left hand and it landed weird and landed wrong. I just got that sharp pain in my shoulder.
It went on from there. It's just one of those things that happened. Unfortunately, it happened right before the fight. You have just got to keep on trucking through.
RingTV.com: I understand from Santos that you sparred two or three more rounds?
RG: Yeah, I did go on and I kept on sparring. When you're in the ring, you're in the ring. At first, you're thinking, "Aw, maybe it's just a little pulled muscle." So I just kept on going.
You know, I went a couple of more rounds and started working my jab, moving and slipping. My head movement was there. I just wanted to see what the outcome was going to be. But I'll just ended up having to take this one on the chin and I'll just keep on rolling.
RingTV.com: Is it true like Santos says that you were in the best shape that he's ever seen you in?
RG: Right now I'm in incredible shape, which is what kind of gets me down. I'm in such great shape and I've never felt this way going into a fight. The diet was right on, and the weight was right on. I mean, I am in really solid shape right now. I'm right there closing in on 140 pounds.
The muscularity is solid where I was right there.Everything was falling into place the way that it should go. Then, the one little thing puts that road block in there. But that's the way that it went. So you've just got to put God first and I just think that it will all work out.
RingTV.com: So are you treating your injury?
RG: Well, right now, I have my arm in a sling. The doctor says to just leave it in the sling and I even have to sleep with the sling on. Because if you toss and you turn, then you can injure it more. It's just that whenever I move around or I make a fast move here or there, it's painful.
So I just keep it in the sling. I will just have to wait until Monday and see what Dr. Dillingham says. He's one of the best guys out there and so we'll just see what he has to say that I need to do to get back onto the road. I can't wait to see what he has to say on Monday so that I can get right back on track.
RingTV.com: What were your thoughts on what Khan wrote on his Twitter account regarding whether or not you were really hurt?
RG: Right now, I'm looking for the best solution to get back into the ring with Maidana, who is one of the best fighters out there. I really wanted that Maidana fight. I was ready to go.
I was taking Maidana really seriously and it was never like,"'hey, let's get by Maidana and go straight to Khan." It's like, "hey, whoever is the best out there, that's who I want. If it's Marcos Maidana, if it's Amir Khan, bring on either one of those guys."
Put it this way, I'm like a wrecking ball — I don't want to go around the building, I want go through the building to get to you if I have to. I'm a fighter. When Amir Khan called me out, as soon as I heard that, I was like, "let's make it happen."
I'm that type of fighter where I'm like, "let's not talk about it, let's do it." But now that I've got an injury, I'm out on the sideline and Amir Khan talking. If Amir Khan is a man of his word, then stop talking and step up.
Then, as soon as I'm ready to rock and roll again, I'm ready to fight anybody in the world, including Amir Khan. Hopefully, Amir Khan talks himself into a contract and signs to fight me.
RingTV.com: Any closing thoughts?
RG: My whole team, the first thing we did after the injury is that we sat back before we made the decision and we said, "let's pray on it." That's what we did. We prayed on it and we made the decision. We put God first before everything.
That's what carries you through, not just the day, but through life, whatever the struggle is. You can be going through whatever. That's the way that I look at it. You've got to go through these trials and tribulations.
So God's like, "you think you're ready, son, but you're not." When I'm ready, I think God's like, "You're going to be shooting like an arrow and you can pierce anything." God closes doors and opens gates.
Lem Satterfield can be reached at email@example.com