"You guys don't know what's going on," Guillen told a cluster of reporters on Friday. "I've been playing with both groins all messed up, both hips all messed up, and that's all I got. I'm the type of guy that likes to play hard. You guys don't know that I've been playing hurt. Both of my hips have been all messed up for three months and none of you guys know anything about it."
Fans booed Guillen in the eighth inning of the Royals' 4-2 win on Wednesday night. He grounded to Colorado third baseman Garrett Atkins and began a slow run toward first base. Atkins' throw was off target, forcing Todd Helton to leave the bag. If Guillen had been at full speed, he might have been safe.
Boos followed Guillen to the dugout.
"I care less about the fans and how they boo me," Guillen said. "They booed me earlier in the season when I was struggling, I could care less. They don't know what's going on with Jose Guillen."
However, Guillen admitted that he was embarrassed by the incident.
"I'm thoroughly against it when I see players jogging down the line and stuff like that," he said. "I don't like that. I was embarrassed myself that day, because I can't give any more than I was giving down the line that day."
Royals manager Trey Hillman said he wasn't bothered by the play in question.
"No, I didn't have a problem, because of the issues I know he's being going through with his lower half," Hillman said. "I told him to be smart with his aggressiveness and his running to make sure he didn't irritate his lower half."
General manager Dayton Moore also came to Guillen's defense.
"He's one of the better outfielders in the game, and the fact that he's DHing would indicate that he's not in the best condition," Moore said. "That's not something that a manager or general manager would announce prior to a series.
"The situation the other night was something that 20,000 people in the ballpark saw. But he's doing the best he can and he's playing through it, he's playing tough."
Hillman said the Royals kept Guillen's leg and groin problems quiet to avoid tipping off the opposition that he might be slow on the bases and in the field.
Guillen said he's been doing exercises and taking treatments to avoid going on the disabled list.
"This is the reason I've been working so hard trying to get better and stay in the field every day, and people don't appreciate that," he said.
"Any other place, I'd probably be on the DL for 15 or 30 days, because I'll bet there's not a lot of players that could be playing the way I'm playing right now. That's the reason I've been DHing. I hate DHing, I don't like DHing."
Guillen hasn't been booed much recently, because he's been the Royals' hottest hitter with a .368 average since May 7. Entering Friday night's game against St. Louis, he was third in American League RBIs with 60 and was tied for the league lead in doubles with 28.
He speculated that if the fans boo him, it would just motivate him to do better.
It was just another day for the outspoken Guillen, who caused a stir on May 28 during a 12-game losing streak by accusing teammates of being "babies."
"I can be a bad boy as long as I want to," Guillen said. "I'm always going to be a bad boy."
Dick Kaegel is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.