SARASOTA, Fla. -- It's become increasingly evident the past few days in the Orioles' clubhouse that the players are anxious for Spring Training to end and the regular season to begin. And prior to Wednesday's game, manager Buck Showalter officially unveiled who would be on the mound for Baltimore to open the 2013 season, giving right-hander Jason Hammel the nod for Tuesday's game in St. Petersburg against the Tampa Bay Rays.

"It's an honor," Hammel, 30, said of the first Opening Day assignment of his career. "Very excited. Basically what it means is I get to be the one to get us off on the right foot. I don't take that lightly. Very confident to come out and win there."

Hammel will be followed by Wei-Yin Chen and Miguel Gonzalez, with Chris Tillman -- who was slowed earlier in camp by abdominal soreness -- scheduled to start either the fourth or fifth game depending on whether he goes to the disabled list. If he does, Tillman would be eligible to come back and pitch the fifth game, but if deemed OK, he will start the team's home opener, April 5 vs. the Twins, instead.

Health was the deciding factor for Hammel this spring, and he worked hard this offseason with the goal of arriving at Spring Training without a knee brace. Battling a right knee injury for most of the 2012 season, Hammel went 8-6 with a 3.43 ERA in 20 games, pitching 118 innings and allowing 45 runs, with 42 walks against 113 strikeouts.

"There were a lot of decisions for him to make last year, whether to have surgery or not, and the whole idea was for him to come back and pitch for us, and pitch into the postseason," Showalter said of Hammel, who had surgery to remove loose cartilage around his knee last July. "That was what his whole offseason was about, was being a guy we can depend on every fifth day. In some cases, every sixth day."

Hammel allowed two or fewer runs in each of his first six starts in 2012, piecing together a 17-inning scoreless stretch in June and being named a Final Vote American League All-Star candidate. Acquired in a February 2012 trade with Colorado in exchange for Jeremy Guthrie, Hammel was a pleasant surprise for Baltimore and went five or more innings in 17 of his 20 starts -- with nine quality starts -- despite the nagging knee issues.

"I'm very happy to say I made it through healthy," Hammel said of his spring, which consisted of a lot of Minor League games so he wouldn't pitch against the team's division rivals. "That was my main concern after last year. It was the first time I dealt with an injury that long, and I feel like I've come back stronger from it. I may not have pitched in many Grapefruit League games [this spring], but I was able to get the work in I needed to."

Hammel hadn't had an ERA under 4.00 in six previous seasons before arriving in Baltimore, and he was demoted to the bullpen in Colorado in 2011. While there, he worked with pitching coach Jim Wright to piece together an impressive final month of the season, and he worked with Orioles pitching coach Rick Adair last spring to rediscover his two-seam fastball.

"It's nice to see the hard work come to fruition," Hammel said. "Things that you've worked so hard for and really not seen the results, and then finally have the switch ... click on and you know, hit the ground running. And now it's something I can hold onto it and continue to improve it. So, I still think the best is yet to come."

Hammel will face a Rays team that drafted him in the 10th round of the 2002 First-Year Player Draft and traded him to Colorado in April '09.