PEORIA, Ariz. -- The Padres essentially finalized their 25-man roster for Opening Day on Wednesday when they acquired right-handed pitcher Ed Mujica and made a handful of other roster moves.

The team still hasn't announced who will earn the final spot in the bullpen, although it appears left-hander Arturo Lopez will break camp with the team instead of righty Luke Gregerson, who was obtained recently as the player to be named from St. Louis in the Khalil Greene deal.

Gregerson, who hasn't pitched above Double-A, will likely begin the season at Triple-A Portland.

The Padres announced on Wednesday that outfielder Drew Macias has been optioned to Triple-A Portland and that first baseman Kyle Blanks, outfielder Emil Brown, catcher Eliezer Alfonzo and pitcher Greg Burke were reassigned to Minor League camp.

Pitcher Justin Hampson was released, though he'll likely sign a Minor League contract. Another pitcher, Jae Kuk Ryu, who was claimed off waivers by the Indians a week ago, was returned to the team Wednesday and subsequently released.

Apparently, according to general manager Kevin Towers, the Indians ran Ryu though a physical and "evidently, they weren't comfortable."

The Padres will open the season with, in order, Jake Peavy, Chris Young, Walter Silva, Kevin Correia and Shawn Hill in the starting rotation. Cha Seung Baek, projected to be the No. 3 starter, will begin the season on the disabled list with a strained right forearm.

Heath Bell will be the closer with Cla Meredith, Mujica, Lopez, Edwin Moreno, Duaner Sanchez and Eulogio De La Cruz.

The Padres will keep 13 position players: catchers Nick Hundley and Henry Blanco, first baseman Adrian Gonzalez, second basemen David Eckstein and Edgar Gonzalez, shortstops Everth Cabrera and Luis Rodriguez, third baseman Kevin Kouzmanoff and outfielders Brian Giles, Scott Hairston, Chase Headley, Jody Gerut and Cliff Floyd.

For all the last-minute shuffling of the bullpen -- Sanchez, Mujica, De La Cruz as well as Hill were all added in the last three weeks -- there weren't many position-player battles to decide spots.

Cabrera, the Rule 5 pick from Colorado, will make the team. He offers speed (something the Padres don't have much of) and gives them an upper-level shortstop who, even if he spends next season in the Minor Leagues, is still seen as worth keeping on the roster for the season.

Cabrera's only real competition in camp for a backup infield job was Chris Burke, who was traded to the Mariners on Sunday.