Cordero appeared to be close to getting his closer's job back. On Monday, the closer pitched in his second game in three days, tossing a scoreless inning against the Braves.
At first, Cordero's fastball was clocked in the high-70s, but by the end of the inning, it was in the high-80s. Cordero acknowledged that in order to return to his old self, he has to play catch a lot more and exercise the arm.
However, after the game, Cordero went back to his hotel room and felt "clicking" in his shoulder. He then called his agent, Larry Reynolds, who then called general manager Jim Bowden. Reynolds and Cordero's father, Edward, were in Atlanta on Tuesday because they were concerned about the right-hander's health.
"We want to make sure nothing is wrong [in the shoulder]," Cordero said. "I don't know if it's anything serious. I told our trainers today and I told my agent there was no pain -- nothing like that."
The Nationals started showing concern about Cordero's shoulder last Wednesday when he pitched against the Mets. His fastball was clocked in the 70s, and he appeared to be hurting whenever he threw a pitch. Cordero said he needed more time to warm up. Since then, he has pitched in two more games.
"He's not in any pain," Bowden said. "He just feels a click. With that being said, he is not quite throwing like he normally throws. It makes sense to get another opinion.
"I do think he is making progress. His arm speed is getting better and his velocity is getting better. I think he is going in the right direction. A click can be normal. A lot of pitchers have it. He has never had it before. We'll check it out and make sure it's OK."
With Cordero not available, reliever Jon Rauch will remain the closer, while Luis Ayala will be the eighth-inning setup man.
In other news, first baseman Dmitri Young went to the University of Miami to have his sprained back examined. Dr. Frank Eismont did not see anything that would require surgery. Eismont feels Young may be helped by chiropractic care and time. There is no timetable on when Young will return to action.
Bill Ladson is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.