"If I'm healthy, I can go 200 innings," Perez said. "I can win a lot of games for this team. When I was a free agent [after the '04 season], I worked really hard. Sometimes, people make you lose your confidence. Sometimes, you think you are doing the right thing to become a better pitcher or a better teammate, but sometimes people take it a different way.
"Even if I'm here at this level -- and I've been here the last nine years -- some people still believe I'm too young to be a veteran. Whatever happened in the past happened in the past. It's a new season and I'm very proud to be part of this Nationals team."
Perez, 30, pitched in his first Major League exhibition game of the season Saturday afternoon with mixed results, giving up four runs in 4 1/3 innings in a 6-1 loss to the Dodgers.
Perez shut out Los Angeles in the first three innings but ran into trouble in the fourth, when he gave up a wind-aided two-run homer to Andre Ethier. Perez was charged with two more runs when left-hander Eude Brito gave up a two-run single to Rafael Furcal in the fifth.
Perez came away believing he had a good outing.
"It was good," Perez said. "I was able to throw my pitches. They took me out of the game because [I reached my pitch count]. Mentally and physically, I'm fine. I'm very good."
Perez wasn't able to compete in a Major League game until Saturday because he didn't have his work visa. He wasn't scheduled to get the visa until March 27, but Jose Rijo, the special assistant to Nationals general manager Jim Bowden, pulled some strings and was able to get Perez's work visa earlier in the week.
"Jose is great, man," Perez said. "He has helped a lot of guys from Latin America come to this team. He is working his tail off to call the embassy for us to get the work visa. We are very proud to have a guy like Jose [with] the Nationals."
Barring an injury, Perez is expected to be in the Nationals' rotation and -- for now -- is on the five-day schedule to pitch in the home opener March 30 against the Braves, but pitching coach Randy St. Claire said that Perez is one of five candidates to pitch that day. Others include Jason Bergmann, Matt Chico, John Patterson and Tim Redding.
'I would be happy to pitch Opening Night," Perez said. "I signed a Minor League contract, but at the same time they are counting on me. If I get to pitch Opening Night, that would mean a lot of goals in my mind. The results have to be good."