While pitching in the fourth inning of the Mets' 3-2 victory over the Yankees, Dickey slipped on his left foot and felt tightness in the muscle. He remained in the game for another inning, but he departed in favor of a pinch-hitter after escaping a bases-loaded jam in the fifth.
After the game, manager Terry Collins said Dickey may have first injured himself taking batting practice earlier this week, but the pitcher said he thought the pain may be unrelated to that. Either way, Dickey hopes to take the mound when his turn comes up again Friday in San Francisco.
"It's sore. I got ice on it and the area's calmed down," Dickey said. "I'm optimistic that it's going to be something I can rebound from.
"We'll just treat the symptoms as we push forward from here."
Dickey has also been pitching the past month and a half with a partially torn plantar fascia in his right foot. He threw five innings of one-run ball in Sunday's game, lowering his ERA to 3.68.
Thomas Boorstein and Anthony DiComo are reporters for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.