With Wednesday's trade of Hayden Penn to the Florida Marlins, the Orioles not only parted ways with their one-time top pitching prospect, but they further solidified their Opening Day roster.

In exchange for Penn, who is out of options and opportunity, the Orioles acquired slick-fielding infielder Robert Andino, who will make the team as a backup shortstop. Orioles president of baseball operations Andy MacPhail confirmed that means the team will go with 13 position players and only 12 pitchers.

It also meant that veteran infielder Chris Gomez was given his outright release as it became clear that he wasn't going to make the Opening Day roster and he had no interest in playing at Triple-A.

"I had been leaning toward 13, but if I had the opportunity to get a 24-year-old bona fide shortstop that can play defense, it was really something I can't pass up," MacPhail said. "As the season progresses, you don't know what twists and turns are going to take place. But we clearly are going to start with 12 pitchers and 13 position players as a consequence of this trade."

Four days before Opening Day, the backup catcher job between Robby Hammock and Chad Moeller, and the final spot on the pitching staff are the only unresolved questions. The Orioles will have to make one more pitching cut with Adam Eaton and Brian Bass among the names likely in discussion.

Penn, a 24-year-old right-hander who made his major league debut in 2005 as a 20-year-old, wasn't going to make the Orioles' roster. He was out of options and the Orioles didn't think they could sneak him through waivers, facilitating the need for a trade. They gave him an opportunity to make the Opening Day roster this spring, but Penn went 0-3 with a 10.05 ERA, allowing 27 hits and walking six in 17 innings.

That meant the end for a once-promising Orioles career for Penn, who struggled with injuries, illness and consistency during his time with the club. He went 3-6 with a 9.31 ERA in 14 career major league starts over parts of three seasons.

"Someone wants me. I'm excited to go over there and pitch," said Penn. "I've had a good time here [and] made a lot of good friends here over the year s, but I look forward to a new start there. I think it will be good for me and I'm excited. Hopefully I get that opportunity and pitch well."

Andino hit .201 (29-for-144) with two homers and 12 RBIs in limited action over the past four seasons with the Marlins. He was drafted in the second round in 2002 and touted as the Marlins' shortstop of the future, but Florida acquired Hanley Ramirez in a trade with Boston in 2005, moving Andino down the organizational depth chart.

Andino is a .258 hitter with 42 homers and 263 RBIs over parts of seven minor league seasons with Florida, but his biggest strength is his defense at shortstop. Andino, who was with the Marlins on their trip on Wednesday to play the Orioles at Fort Lauderdale Stadium and needed only to switch clubhouses, is batting .203 with one homer and five RBIs this spring.

"We felt like he really solved an issue for us in terms of the final composition of our team," MacPhail said. "He's going to get more opportunity to play now because he's not behind Hanley Ramirez. I'm sure we're going to get an opportunity to see him more, move him around. But the attribute that was attractive to us was the defensive ability to play up the middle."