The suit filed last month in the Superior Court of California in San Francisco seeks unspecified damages.
The lawsuit claims that someone created a false account under La Russas name and posted updates, known as tweets, that gave the false impression that the comments came from La Russa. The suit says the comments were derogatory and demeaning and damaged La Russas trademark rights.
The account bearing La Russas name is no longer active.
Messages left Thursday with La Russas attorney and San Francisco-based Twitter were not returned.