Luis Castillo walked into the Phillies clubhouse and placed some of his belongings at his locker. Before he had even begun changing into his uniform, the 35-year-old second baseman was summoned to an office across the hallway from the clubhouse.

Moments later, he was on his way out, looking for a job.

The Phillies ended their brief experiment with Castillo by releasing him Wednesday, a move that cleared the way for Wilson Valdez and Michael Martinez to take over second base in the absence of injured Chase Utley.

The slick-fielding Valdez will start at second Friday when the Phillies open the season against Houston at Citizens Bank Park. This is only the third time Valdez will be on an opening-day major-league roster and the second time he will start in an opener. His last opening-day start was for Seattle in 2005.

"I'm grateful for the opportunity they're giving me," the 32-year-old Valdez said.

The Phillies finalized their roster by reassigning infielder Delwyn Young and catcher Erik Kratz to the minor leagues. Infielder Pete Orr edged out Young for the final bench spot.

That means the opening-day roster has 12 pitchers, two catchers, six infielders, and five outfielders.

Although he is a career minor-leaguer, the 28-year-old Martinez made enough of an impression on the Phillies to make the opening-day roster, which ultimately cost Castillo his chance to make the team. Ironically, Castillo was coming off a solid performance in Tuesday's exhibition win over Pittsburgh with two singles, two runs, an RBI, and a stolen base.

"It wasn't an easy decision," Phillies general manager Ruben Amaro Jr. "He [Castillo] was extremely professional. He was well liked in the clubhouse. We kind of liked everything about him. We just felt we're comfortable with the people we have here to move forward. It's more a testament to the people that are here and the job they've done so far this spring."

The Phillies brought in Castillo after he was released by the New York Mets late in spring training. He played seven games, and it seemed he had a good chance of sticking with the team. His career .368 on-base percentage also intrigued the Phillies, who may be forced to manufacture more runs with Utley gone indefinitely and Jayson Werth now with Washington.

But Valdez, who started a career-high 88 games last season, showed his versatility by capably filling in for Jimmy Rollins at shortstop and for Utley when the two went down with injuries last season.

"Valdez played such a good role for us last year, and he can play multiple positions, and so can Martinez," manager Charlie Manuel said. "Martinez and Wilson can play all the outfield positions. I played Wilson in center field in spring training, then put him in right. I definitely can trust him in the outfield."

Arguably, Valdez is a defensive upgrade over Utley, but neither he nor Martinez has been an everyday player in the majors.

"He can play for a period of time for you," Manuel said of Valdez. "He does get a little tired. You've got to monitor when he gets tired. He's a very productive player. He steals, and he hits better than people realize. He can get big hits for you."

By deciding on Martinez over Castillo, the Phillies have a faster and more versatile player but one who has yet to prove he can play at the major-league level. The 5-foot-9, 145-pound Martinez batted .239 with a .257 on-base percentage during the spring. Still, Manuel sees value in the energetic Dominican.

"I think Martinez is an interesting guy because he is talented," Manuel said. "He can run. He can throw. He has a great arm. He has tremendous agility. He's acrobatic. He hasn't proved he can hit in the big leagues yet. But I think he can hold his own because of his talent and because of the type of team he's on. He has the talent to be a good big-league player."

The Phillies chose Martinez in the annual Rule 5 draft in December. Washington originally signed him as an undrafted free agent in 2005. His next major-league game that counts will be his first.

Martinez opened Manuel's eyes with dazzling plays at shortstop in an exhibition game against Detroit in Lakeland, Fla. But he's been around the minors long enough to know he couldn't take for granted that he would be on the Phillies' opening-day roster.

"Those plays I made didn't change anything," Martinez said through third-base coach Juan Samuel, who acted as his translator. "I knew I had to keep plugging and show what I can do. I know my role as a player is to continue to improve. I thought I was going to be able to make it to the major leagues, but I have no idea why it took so long. I thought I had the talent."

Contact staff writer Ray Parrillo at 215-854-2743 or