Cordero does not need to go on the disabled list. Instead, the righty will pitch and continue to strengthen his shoulder through various exercises designed in conjunction with the Nationals' athletic training staff.
Cordero is expected to rejoin the Nats on Wednesday.
"We were very pleased," general manager Jim Bowden said. "Dr. Andrews was encouraged. He said [Cordero] has weakness, and he needs to build it up. There is no reason to disable him -- just get him to work harder to build up the arm strength."
Cordero appeared to be close to reclaiming his closer's job. On Monday, the reliever 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 even acknowledged earlier in the week that in order to return to his old self, he has to play catch a lot more and exercise the arm.
However, after Monday's game, Cordero went back to his hotel room and felt "clicking" in his shoulder. He then called his agent, Larry Reynolds, who called Bowden. Reynolds and Cordero's father, Edward, were in Atlanta on Tuesday, because they were concerned about the right-hander's health.
The Nationals started showing concern about Cordero's shoulder last week, 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.
Meanwhile, the Nationals are hoping that first baseman Dmitri Young (sprained back) and outfielder Elijah Dukes (right hamstring sprain) will start playing games within seven to 10 days. Young is in Washington getting his treatment, while Dukes is in Viera, Fla.
"We are going to make sure they are 100 percent before we put them back on the field," Bowden said.
Catcher Paul Lo Duca (right hand contusion) took dry swings on Wednesday, and he didn't feel any pain. He will try to hit off a tee on Thursday.
Bill Ladson is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.