The Nationals played Monday without Bryce Harper, who has swelling in his left knee.
Harper's injury was aggravated in Sunday's 6-1 win over the Phillies and he had an MRI. Team medical director Wiemi Douoguih said the outfielder has inflammation of the bursa sac in front of his knee, which he anticipates "clearing up in a couple of days."
The MRI showed some soft tissue swelling, but no structural damage, Douoguih said.
Mariano Rivera wasn't prepared for the question. He didn't have a baseball, so a man wearing a Mets caps tossed him a pristine ball, and the great closer happily showed off the grip that has made him the major-league's saves leader.