TEMPE, Ariz. -- Francisco Rodriguez might be the most accomplished rookie in major league history.

Many heralded prospects have tantalized teams during late-season callups, then had to prove themselves again the next year. Now Japanese slugger Hideki Matsui and Cuban pitcher Jose Contreras face questions about how they'll adjust to the competition against the best baseball players in the world.

Rodriguez already has answered such concerns.

On baseball's biggest stage, no less.

The 21-year-old pitcher nicknamed "K-Rod" quickly made his mark last October. He tied a major league record with five postseason wins, set a relief record with 28 postseason strikeouts, posted a 1.93 ERA and became the youngest pitcher ever to win a World Series game.

"That's in the past," he said. "I have to live in the future. I need to have a good year and help the team as much as I can."

Rodriguez is a rookie because he only pitched 5 2-3 innings last September. He was eligible for the postseason roster because of a loophole in the rules that allows for teams to replace players on the disabled list with a player on their 40-man roster.

Instead of just getting a taste for the majors like most late-season callups, he performed in the highest-pressure spots.

"He pitched in the toughest situations you can be in," manager Mike Scioscia said. "He did it for six weeks. We're looking for consistency. If Frankie Rodriguez shows the consistency he showed in the playoffs, he'll be fine. That's the challenge for all young players -- being consistent."

Unlike most rookies, Rodriguez comes with a lot of advance billing. Opposing players watched him overpower some of the game's toughest hitters last October with his 95 mph fastball and nasty, late-breaking slider.

A successful at-bat against Rodriguez could be the highlight of a young player's spring -- the opposite of last March, when Rodriguez tried to impress his team.

"From last year to this year is a big difference," he said. "Last year, nobody knew me. Now when I pitch, people know who I am because of what happened in the playoffs. It feels a lot different.

"Guys are swinging a lot more on the first couple of pitches. They don't take too many pitches. They try to be aggressive and swing early in the count. They don't want to go deep in the count and fall behind. I like to be aggressive, but I have to mix it up more early in the count."

That's just one of the many adjustments Rodriguez will have to make this season. Opposing scouts have spent hours breaking down video of Rodriguez, trying to learn his tendencies and weaknesses.

Rodriguez will also have to learn to deal with the ups and downs of a 162-game season.

"He just needs to be himself. He's very competitive and throws strikes," Anaheim general manager Bill Stoneman said. "He has good stuff. All he needs to do is go out and compete. Things won't always go as easily for him as they did in the playoffs. He'll hit some rough spots. But overall, if he stays consistent, he'll be good more than bad."