Matt Belisle has been diagnosed with a right calf strain.
Matt Belisle was pulled from an appearance Tuesday because of an apparent injury.
Nationals purchased the contract of RHP Matt Belisle from Triple-A Syracuse.
Matt Belisle can opt out of his minor league contract on Sunday.
Matt Belisle injured his calf at Saturday's workout.
Nationals signed RHP Matt Belisle to a minor league contract with an invitation to spring training.
Matt Belisle will undergo arthroscopic surgery on his right elbow on Monday.
Cardinals activated RHP Matt Belisle from the 60-day disabled list.
Matt Belisle (elbow) recently threw live batting practice and will do so again in the next few days.
Matt Belisle (elbow) threw another successful bullpen session on Friday.
Matt Belisle (elbow) threw a bullpen session Friday.
Matt Belisle (elbow) has been cleared to ramp up his flat-ground throwing after visiting with Dr. James Andrews.
Matt Belisle (elbow) has been sent to receive another opinion from Dr. James Andrews.
Matt Belisle (elbow) resumed playing catch on Tuesday.