WASHINGTON -- If Garrett Mock had his way, the baseball season would have started already. The right-hander badly wants to show he belongs in the Nationals' starting rotation this season.

"I wish we could play 365 days a year," the giddy Mock said by phone. "Of course, that would be tough on my arm. But why not? Baseball is the best game ever."

Mock, 24, has reasons to be psyched. For the first time in his professional career, Mock has a healthy left knee. He also had a strong showing in the Arizona Fall League. In his first seven appearances for the Peoria Javelinas, Mock gave up six runs in 23 1/3 innings, posting a 2.33 ERA. That impressive showing was enough to land him on Washington's 40-man roster.

"I had to step up and get through last year without dropping my head. I'm trying to take advantage everything that I have," Mock said. "It's just about me being healthy."

Assistant general manager Mike Rizzo watched Mock in the AFL and was impressed with what he saw.

"Garrett was outstanding," Rizzo said. "He looked as good as any pitcher in the Arizona Fall League. His knee looked very healthy. His arm was working good. He was throwing strikes."

When the D-backs drafted him in the third round of the 2004 First-Year Player Draft, Mock was already damaged goods. He hurt his left knee while playing at the University of Houston that year. He originally injured his left fibula and missed a few starts. However, the fibula injury forced Mock to change his mechanics. Unfortunately for him, the changes ended up damaging the knee.

"Instead of landing straight, I had to start landing [in an awkward way]," Mock said. "I had to turn my foot in a very awkward way to throw the ball."

But during his two plus-years in the D-backs organization, Mock didn't have surgery to repair the knee. Instead he gutted it out. In fact, he won 14 games for Class A Lancaster in 2005, but had a tough time doing any kind of running.

On Aug. 7, 2006, Mock and left-hander Matt Chico were traded to the Nationals for right-hander Livan Hernandez. Washington general manager Jim Bowden made the deal to improve the farm system.

At the time of the trade, Mock was considered the better player and was on the fast tract to the big leagues. But after four starts and giving up 19 runs in 16 1/3 innings for Double-A Harrisburg, Mock had arthroscopic surgery to repair the knee. The Nationals were aware of the injury when they traded for Mock, but they still thought he was worth the risk.

"I was supposed to make it by leaps and bounds and get to the big leagues pretty fast," Mock said. "Now, after going through a year of surgery, rehab and all that stuff, I haven't done anything to reach my own expectations.

"The injury I had with my knee, there were certain things I could not do. I couldn't use my fastball the way I wanted. I had to tweak my mechanics to where I could use the fastball."

Mock thought he would reach those expectations in 2007, but the knee still wasn't healthy enough to start the season on time. He only appeared in a combined 15 games and went 2-7 with a 5.12 ERA for the Gulf Coast Nationals and Double-A Harrisburg. By the end of the Minor League season, however, Mock felt injury-free and could pitch the way the way he wanted to. By the time he got to the AFL, he was able to get hitters out on a consistent basis.

"The main thing was, I was healthy and I could trust my knee," Mock said. "On top of that, I was getting my mechanics smoothed out. I'm not worried about how my knee feels."

Now, Mock want to show that he belongs in the big leagues.

"Hopefully all my dreams will come true and I get to play in the big leagues," Mock said. "I hope to stay for a long time. You are not going to find too many people that enjoy baseball the way I do."