Major League Baseball fans have watched intruders come onto the field or seen players struck with objects thrown from the stands. Just this spring, a naked man ran onto the new Citi Field during a New York Mets game.
In 2003, at Chicago's U.S. Cellular Field, a fan tried to tackle umpire Laz Diaz, a former Marine. Earlier, at the same venue between the same teams -- the White Sox and Royals -- a father and son attacked Kansas City Royals' first-base coach Tom Gamboa.
In Oakland, Calif., that same year, a 24-year-old fan allegedly hit right fielder Carl Everett of the Texas Rangers in the back of the head, throwing a cell phone at him from the second deck. Everett was not hurt, but the man was charged with assault with a deadly weapon.
In another incident, Padre third baseman Sean Burroughs was hit from the stands in Chicago with a cell phone.
ABC's information specialist Brad Martin contributed to this report.