According to Perez, it all has to do with his right knee -- the one that possibly led to a 6.82 ERA in 14 starts last season and was then operated on in September.
For pitchers this time of year, not only do games not count, but there are no games to begin with, and sometimes there aren't even any hitters to face when throwing off the mound.
So while Mets manager Jerry Manuel has been raving about Perez's two bullpen sessions in the early part of Spring Training, what deserves more attention is what Perez is saying about that once-troublesome knee.
"When I throw [a] bullpen [session], the next day, I just wake up as if I had pitched in a prior game," Perez said in Spanish after his Saturday workout at Tradition Field was shortened because of a threat of rain. "It's just normal soreness. That's what has me pleased -- that I haven't felt any severe pain.
"First and foremost, I'm just happy to be healthy, and I've prepared myself hard for this time of year to be on par with everybody else."
Perez has always had the talent, but some would say he's previously lacked the makeup -- things like dedication, smarts and grit. This Spring Training, though, the Mets have tried to pair the 28-year-old up with ace Johan Santana, and Perez sought out the advice of Hall of Fame southpaw Sandy Koufax, who told him recently to not think too much and "just throw the ball" -- on top of a few other things.
The Mets need Perez to bounce back. They were unable to sign a legit starting pitcher this offseason, and they still owe Perez $24 million for the next two years. So all aspects of his game -- the mental part as much as the physical -- need to be right if the Mets are to avenge a 92-loss season.
But once again, it all starts with Perez's knee.
"I thought last year, he was just hurt; he wasn't able to get up here and pitch," Mets general manager Omar Minaya said. "But his knee is healthy, and to me, my main concern is his knee. I think when his knee is fine and he's able to do things like anybody else, he should be fine.
"He's feeling much better right now. He's able to get across his knee and all that other stuff."
Perez broke out with the Pirates in 2004, when he finished with a 2.98 ERA in 30 starts. He was then dealt to the Mets along with Roberto Hernandez for Xavier Nady in July 2006, and had a nice first full season with the Amazin's, going 15-10 with a 3.56 ERA in '07.
Then, a 2008 campaign that saw him go 10-7 with a 4.22 ERA landed him a three-year, $36 million contract.
Perez returned to Mets camp -- after representing Team Mexico at the World Baseball Classic -- last year out of shape. Then, after giving up 24 runs in his first 21 2/3 innings of that regular season (a 9.97 ERA), he was placed on the 15-day disabled list with right knee tendinitis and didn't return until early July.
Things didn't get much better thereafter. After getting tagged for six runs in two-thirds of an inning against the Phillies on Aug. 23, Perez underwent surgery for patella tendon tendinitis on Sept. 1.
"I wasn't feeling 100 percent, and I was trying to compensate for [the knee injury] by doing other things differently," Perez said. "Unfortunately, it didn't work. They operated on me and here I am. Thankfully, I'm healthy and ready."
Perez said he's ready mainly because of some of the most intense workouts of his eight-year career. He spent the entire offseason training at the Fischer Sports Physical Therapy and Conditioning in Phoenix, except for the two weeks he spent in his native Mexico -- "those weeks flew," Perez said -- and, thanks to that, he believes he's primed for a bounce-back season.
"I was ready for that," Perez said about the intense training. "I wanted to really get ready for this year."
Perez has shown that early with a couple of impressive bullpen sessions. After his latest one on Thursday -- one that included actual professional hitters, who are still trying to get a feel for live pitching nonetheless -- Manuel said it was "the best we've seen [since] we've had him."
Early, yes. But a good start for a pitcher and a team that really need one.
"This is a year that's very important for me and for the entire team," said Perez, who is scheduled to throw batting practice again on Sunday.
"This year is important, simply because of what's happened to us the last few years. Everybody is healthy, which is the most important thing. And I feel like we owe something to the fans of New York."
Alden Gonzalez is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.