FORT MYERS, Fla. -- For Johan Santana, a birthday means the same thing to him as it does to anyone else.

"It's just another year," Santana said. "Just like anybody else, I get old, too."

Old might be a relative term when you talk about Santana, who celebrated his 28th birthday on Tuesday. For a pitcher who is considered to be just reaching the prime of his career, Santana has already achieved plenty of success, including two Cy Young Awards in the past three seasons.

So far this spring, Santana hasn't shown any signs of slowing down, lowering his ERA to 1.00 in his third Grapefruit League start Tuesday. Santana pitched four scoreless innings against the Cardinals in the Twins' 5-2 victory and gave up just two hits while walking two and striking out four in the contest.

But with it being his birthday, questions started to arise as to just how long Santana envisions himself being able to stay in the game. Considering other successful pitchers who have pitched past the age of 40 -- like Boston's Curt Schilling, who turned 40 in November -- the question was posed to Santana if he would like to remain in the game long enough to reach that age.

"If I'm healthy, why not?" Santana said. "I love this game, so if I stay healthy and have a chance to pitch for that long, why not? You focus on staying healthy, and hopefully over the years you get better and can stay on this level for a long time."

For Santana, the key to a successful career is not just longevity but a chance to improve as he gets older. But at times, it is hard to envision improvement for a pitcher who has already been regarded by many people around baseball as one of the best in the game.

"He's the best left-handed pitcher in the game," Twins manager Ron Gardenhire said. "Can I say he's the best pitcher in the game? Yeah, I can say that, too."

Still, Santana believes there's room for him to develop. Whether that means getting off to a quicker start, as Santana has shown a tendency to pitch his best after the All-Star break, or just being more successful in a certain at-bat, Santana feels there is a lesson in everything that he does.

But more important than looking ahead, Santana is more focused on how he's feeling right now. Getting ready for this season is his primary focus and so far, that mission is going as planned.

"It's coming along pretty good," Santana said. "My arm strength is there. I'm missing up with my fastballs a little, but I just have to get everything going. Right now I'm feeling much better, so I'm making progress."

Setback No. 2: First baseman/DH Ken Harvey's chances of making the Twins roster practically disappeared Tuesday with the news that he will undergo arthroscopic surgery on his right knee and miss four to six weeks.

The Twins medical staff discovered something floating around in the knee joint and decided to send Harvey back to the Twin Cities for the surgery.

Harvey returned to the Twins lineup on Monday after missing most of the spring with a pulled chest muscle. But in his return, he re-aggravated the injury. Though the news of surgery wasn't the best-case scenario, at least the Twins feel that the time off will give the chest muscle a chance to heal.

"It's unfortunate because it looks like he could swing the bat," Gardenhire said.

The Twins only got to see Harvey in a total of four at-bats this spring, though he recorded hits in two of those appearances.

A new track: The Twins continued to reduce their number of pitchers in the second round of roster cuts Tuesday.

Left-hander Errol Simonitsch was optioned to Triple-A Rochester and left-hander Jose Mijares to Double-A New Britain. The club has continued to ship out some of its young arms in an attempt to give a few other pitchers more innings during game action. One pitcher the Twins want to see more of is right-hander J.D. Durbin.

Durbin threw a scoreless ninth inning against the Cardinals on Tuesday and earned his first save of the spring. With Durbin in the running for a relief spot and out of options, the Twins want to see how his arm can bounce back in consecutive outings.

The chance to pitch back-to-back days won't come immediately, as Durbin will not make the trip to Tampa on Thursday. But the opportunity to work out of the bullpen frequently is one that he appreciates. Having spent nearly his entire career as a starter, the adjustment to the bullpen is something Durbin feels will only take time.

"I want the experience," Durbin said. "I want to feel comfortable. That's the biggest thing about being in spring camp, is feeling comfortable."

Meeting day: Twins players spent most of their morning in the clubhouse for a meeting with the Players Association union chief Donald Fehr and his staff.

On the agenda for the meeting was to discuss the recent Collective Bargaining Agreement that was passed this offseason. Twins player rep Michael Cuddyer said that getting the CBA approved so quickly was a huge advantage rather than having it drag into the spring.

"It went real smooth, and we obviously got the deal done early," Cuddyer said. "It's nice to have it done and know that we have five years left of it."

Twins tidbits: Alejandro Machado (tendinitis in right shoulder) has continued to progress in his throwing routine and told Gardenhire he feels he could be ready to return to game action in four to five days. ... The Twins set a Spring Training record for attendance during Tuesday's game against the Cardinals with 8,134 fans. The previous record of 8,091 was set on the same date back in 2000. ... Matt Garza is scheduled to back up Sidney Ponson in Friday's game against the Orioles in Fort Lauderdale. Ponson is expected to pitch four innings and Garza likely will see three. ... With the two cuts Tuesday, the Twins now have 49 players in camp, including 24 pitchers, five catchers, 12 infielders and eight outfielders.

Coming up: The Twins head to Tampa on Wednesday for their second game of the spring against the Yankees at Legends Field. Carlos Silva will get the start against right-hander Jeff Karstens in the 6:15 p.m. CT contest.