Last season, Perez, 31, played for Washington and exceeded expectations. He delivered 14 quality starts and had a respectable 4.34 ERA.
"[Perez] has done a very god job," manager Manny Acta said last September. "He has given us a lot of quality starts and the innings that we were hoping he would give us out of Spring Training. We think he could have easily won double-digits, almost 15 wins, with any type of help."
Perez made $850,000 in 2008, a huge pay cut from the $7.7 million he made while pitching for the Royals in '07.
General manager Jim Bowden was not available for comment.
Bill Ladson is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.