Contreras had a record of 117-50, with a 2.82 ERA in Cuban league play, including a 13-4 record and league-best 1.76 ERA in 2002. His fame in the U.S. started with the eight shutout innings he pitched against the Baltimore Orioles during a televised exhibition game from Havana in 199. In that game Contreras allowed just two hits and struck out 10, including Albert Belle twice.
CUBA