"He was a big help for me last year," the Cubs' first baseman said of Castro. "He'd see me in the tunnel being real mad, and he'd say, 'Don't worry about it, you're better than this.' We need that every day, every play, every pitch."
Cubs manager Rick Renteria has also liked what he's seen from Castro, who went 2-for-2 in the Cactus League opener on Thursday, including a two-out RBI double in the third. Renteria complimented Castro's defense on a double play.
After a season which was nothing but a struggle for the shortstop, what does Renteria expect from Castro this year?
"I hope to see basically a young man who is trying to put himself back on the level of playing that he did a few years ago," Renteria said of Castro, a two-time All-Star who scuffled last season, batting .245. "That kid is still there.
"The reality is he's been working really hard," Renteria said. "He's been working with [coach Gary Jones] very hard, and obviously, he's worked with everybody. I just hope he comes out and starts to enjoy himself a little more again, play the game the way he's capable of playing by maybe releasing some anxieties he may or may not have had, I don't know.
"The reality is, he knows all our eyes are on him, and they're on him not because we're looking to hammer him, but they're on him because we want him to do well."
The daily sessions with Jones have focused on footwork as the new Cubs infield coach tries to help Castro reduce the mistakes. Past Cubs coaches have also done extra work with the shortstop, who has led the National League in errors each of the last three seasons, and finished second in his first abbreviated season in 2010.
"It's pretty good work, and we work every day," Castro said of the early sessions with Jones. "It's a good routine -- attack the ball."
It's not as if Cubs coaches in the past haven't worked with Castro on his footwork. They have, but it didn't click.
"With Jonesy, we work a little more," Castro said. "We did footwork with other [coaches], too, but it was different work. [Jones] wants the left foot in front [when I throw], and you can stride to first base."
The scheme makes sense to Castro.
"I feel more comfortable," he said.
The Cubs are hoping that comfort level and Renteria's nurturing can get Castro on track offensively. He batted .300 in 125 games in 2010, then hit .307 in '11 and .283 the next season. Last year, he struck out a career-high 129 times.
"He's been working and his body language looks good," Renteria said of Castro after Thursday's game.
"He told me to be comfortable and play the game the way you've always played -- be yourself," Castro said of the advice.
Does he feel good so far?
"Oh, yeah, big time," Castro said. "That's what I want, is to be me. I know if I make a mistake, I know I don't feel good. I'm trying to be consistent."
Castro and Rizzo are key pieces to the Cubs' plans. Both were given long-term contracts -- Castro received a seven-year, $60 million deal in August 2012 and Rizzo got a seven-year, $41 million package last May. Castro turns 24 on March 24; Rizzo is 24.
"We talk a lot," Castro said of Rizzo. "We have a good relationship. We try to help each other. If I have to say something to him, I tell him, and if he has to say something to me, he'll tell me. That's pretty good -- that's the type of people you want around you."
Both talked about how they want to put last season behind them.
"We're getting ready for this year," Castro said. "Last year's over. We're working hard here in Spring Training to be ready for the season and have a good season."