The injury occurred in the eighth inning, when Nationals second baseman Danny Espinosa's foul ball hit Ruiz's wrist.
"It's a little bit sore, but it's normal," Ruiz said. "I think I can play [Thursday]."
Ruiz, the Phillies' hottest hitter this season, went 3-for-4 with a double. He entered the game leading all National League catchers with seven home runs, 29 RBIs and 71 total bases. His average rose to .357 on Wednesday.
"It was fun," Ruiz said. "I had a great time [Wednesday]. I told myself to be relaxed and have good at-bats. It was exciting."