"This guy is an athlete," Baker said after Choo's first two Cactus League games. "He has a lot of pride. He works hard. He'll be fine. We just have to preserve his legs."
That may be so, but a lot is working against Choo, who headlines a small contingent of players going against the grain this spring. While there is nothing odd about position changes, a 30-year-old shifting to a tougher and unfamiliar spot is rare.
Most transitions follow certain patterns along the defensive spectrum popularized by statistical guru Bill James. The spectrum lays out the positions on the field -- minus pitcher and catcher -- from left to right, going from easiest to handle (first base) to hardest (shortstop).
As players age, they tend to slide to a corner. Think Cal Ripken going from shortstop to third base, Carlos Beltran from center field to right field or Alfonso Soriano from second base to left field. Then there are catchers, such as Mike Piazza and Victor Martinez, who became part-time first basemen.
When players swim upstream, they usually are young, returning to an old stomping ground, or both. Such is the case this spring, when the Phillies' Michael Young and the D-backs' Martin Prado are shifting back to third base, while the Rays' Desmond Jennings and the Yankees' Brett Gardner are moving back to center field. Gardner has spent most of the last three years in left, but he was a regular center fielder in 2009 and played there almost exclusively in the Minors.
"I feel comfortable out there. I feel more comfortable going out there than I would to left field," Gardner said last week. "Probably always will, even if I play left field for six or eight more years."
Last season's most publicized move occurred in Detroit, where Miguel Cabrera manned third base regularly for the first time since 2007, reversing his previous switch to first. While advanced metrics pegged Cabrera as below average at the hot corner, he made it through 154 games there, won the Triple Crown and the American League Most Valuable Player Award and advanced to the World Series.
But what happens when a new position is more difficult, and also completely foreign? That's the challenge facing the Cardinals' Matt Carpenter.
Carpenter came through the Minors as a third baseman and has seen time at first and in the outfield for St. Louis. Last season, he played five games at second base -- his first there since age 13, he estimated -- then went into the winter with instructions to get up to speed at the position, so the club could try to work his bat into the lineup.
The 27-year-old devoted his offseason to the task, taking copious grounders and double-play turns, refining his mental approach and preparing with extensive video study of Gold Glovers Robinson Cano of the Yankees and Brandon Phillips of the Reds.
"I kind of feel like a kid all over again, because you watch these other big leaguers and you try to be just like them," Carpenter said earlier this month. "We're watching the unique techniques. Everybody does something different. We practice it all and try to figure out what I'm going to be the best at, and where I'm going to be most comfortable."
There is precedent for the move within the St. Louis organization, which converted Skip Schumaker from outfield to second base in 2009. Schumaker, now with the Dodgers, experienced a steep learning curve, and even four years later, continues to work at it.
"I played outfield my entire career, so I feel like I still need more reps in the infield," Schumaker said last week. "It was a mental grind at first, because you don't want to be the guy making mistakes, messing up a Chris Carpenter ground ball. I took it very serious. It's still a work in progress, because the outfield comes more natural to me, but I'm fortunate to go back and forth."
Schumaker, of course, isn't the most famous or extreme of the Cardinals' recent position changes. That would be Rick Ankiel, who reemerged as a power-hitting outfielder in 2007 after his promising pitching career hit a dead end.
Ankiel, now with the Astros, served as a source of encouragement when longtime big league pitcher Micah Owings was considering a similar switch this offseason. The 30-year-old Owings ultimately signed a Minor League deal as a first baseman with the Nationals, on the strength of his career .502 slugging percentage and nine home runs.
For Owings, the switch represents a second chance.
"I had some success in the league as a pitcher. I was very fortunate and blessed by that," he said. "But I feel I have some more talent in me that I want to challenge myself with. I want to contribute to a team, in this case the Nationals. Fortunately, I have an opportunity, and let's see what happens. I just want to get my full potential out and see where it goes."