The New Jersey governor then got booed loudly Tuesday night.
The ovation quickly turned sour after Christie stood up and slapped hands with another fan. No matter that Christie gave the souvenir to a kid.
Christie was sitting in the third row, near the New York dugout. In the third inning, St. Louis rookie Paul DeJong lifted a high foul that bounced in the stands, and Christie reached out with his left hand and snagged it.
The embattled Republican recently tried out for a spot on popular sports talk radio station WFAN in New York.
The Cardinals beat the Mets 5-0.
The Associated Press contributed to this report.