Maradona, taken to Los Arcos clinic during the early hours, was not seriously hurt and was expected to return home later in the day, the broadcaster Cronica said.
Doctors from the clinic — where Maradona was hospitalized in 2007 with toxic hepatitis from drinking — were scheduled to hold a news conference at noon local time to provide details of the injury and the treatment.
Witnesses said Maradona was bleeding close to his mouth when he arrived at the clinic with his girlfriend. La Nacion newspaper reported on its website that the bite was to Maradona’s upper lip.
Maradona, 48, a gifted player who led Argentina’s team to its second World Cup victory in 1986, is worshipped in Argentina despite years of scandal involving drug addiction, overeating and alcoholism.
He retired from professional soccer in 1997 and almost died from cocaine-induced heart problems in 2000.
In 2008, despite concerns over his continued substance abuse, explosive conduct and lack of coaching experience, he talked his way into the job as coach of the national team.
Although his coaching record has been spotty — Argentina barely squeaked into the World Cup finals— the team is now among the favorites to win.