What will the Tigers get out of Nick Castellanos?

The highly-touted rookie has been given a starting role, and will be the most-watched player on the field in the first days and weeks of the season.

Nick Castellanos became the first Opening Day rookie starter for the Tigers since second baseman Scott Sizemore in 2010, and went 2-for-4 in that game on Monday.

Rick Osentoski / USA TODAY Sports

DETROIT -- What will the Detroit Tigers get out of third baseman Nick Castellanos this year? The highly-touted rookie has been given a starting role, and will be the most-watched player on the field in the first days and weeks of the season.

"He's a big key for us," said Detroit Tigers Hall of Famer Al Kaline, now a special assistant to general manager Dave Dombrowski. "Without putting pressure on him, somebody has to step up at the bottom of our lineup."

Castellanos, 22, became the first Opening Day rookie starter for the Tigers since second baseman Scott Sizemore in 2010, and went 2-for-4 in that game on Monday. He got thrown out trying to stretch a single into a double against Kansas City Royals left fielder Alex Gordon -- who has one of game's best outfield arms. He also failed to pull down a pop foul that was playable. However, he delivered a clutch single in the ninth inning to put the eventual winning run on third base.

That game likely provided an accurate look at what to expect from Castellanos: brilliance with one swing and head-scratching with his next move.

"In the first couple games there have been some growing pains for him," Tigers manager Brad Ausmus said after Wednesday's 0-for-3 with a walk. Royals crafty lefty Jason Vargas, who tends to be tougher on right-handed hitters like Castellanos, constantly got ahead of him and kept him off-balance.

Ausmus was impressed with what Castellanos did as a hitter in spring training, when he batted .333 with nine doubles, two homers and a team-high 16 RBIs. But the manager cautioned about the challenge that lies ahead with pro scouts, pitching coaches and pitchers breaking down everything in his swing and approach.

"They'll find your weakness," Ausmus said. "And it looks like he's using the whole field well. But make no mistake about it. There are very few Mike Trouts ... it's a rare mold. We haven't seen anything like him."

Trout, now 22, never missed a beat upon arriving in the majors two years ago and entering into MVP conversations with Tigers first baseman Miguel Cabrera.  However, even Cabrera, the 2012 Triple Crown winner, needed a couple years to become a .300 hitter. He batted .268 as a rookie in 2003 for the Florida Marlins, and .298 in his first full season in 2004 at age 21.

Kaline went on to amass 3,007 hits, but batted .276 with little power in his first full season in 1954. Kaline was only 19 that season and led the league at .340 the following year.

Castellanos had 18 at-bats last September and is hitting .280 without an extra-base hit in his first 25 at-bats in the majors. He will undoubtedly get stronger and wiser, but it will come down to the chess match to be played with the best pitchers he has ever faced.

"He's always been able to hit since we signed him," Kaline said. "But now it's going to be a matter of knowing how pitchers pitch him. Now, they are going to have a line on him. Now, it's up to him to figure it out on his own. That's always the toughest part for young kids. But he's a smart hitter, and I do not see him having any problem making adjustments."

Castellanos said that he realizes the challenge ahead, but does feel up to it.

"Adjustments are what it takes to be successful at any level of baseball," he said. "It's just that the higher you go, the more adjustments you have to make. In the big leagues, everything's a lot quicker."

While Castellanos might seem somewhat over-matched at times this year, he has raw ability that turns heads. I was watching batting practice before a spring training game in Tampa while conversing with New York Yankees Hall of Famer Reggie Jackson, who stopped to focus on the batter spraying balls to all fields with authority.

"Who's that kid there?" Jackson asked. "He's really got some pop in his bat."

When told it was Castellanos, Jackson wanted more information on his background. I relayed that comment to Castellanos, who beamed and said, "Really? That's great."

But will he be great? And will the Kalines and Jacksons still be talking about him two seasons from now? That's his challenge.

He wore No. 30 last year, but requested No. 9 this season. Single-digits go to a team's best players.

"I wanted the number for my son, Liam, who was born last year on Aug. 1," said Castellanos. He explained that he took the eighth month and the first day and added them together to come up with nine.

 "Liam's a cool kid," added Castellanos, who could be found cradling him after nearly every Grapefruit League game. He's engaged to Liam's mother, Vanessa Hernandez, and is planning a January wedding.

But there's a season of baseball to be played first, and Castellanos continues to spend extra time with infield coach Omar Vizquel, an 11-time Gold Glove winner, and hitting coach Wally Joyner, who had 2,060 hits in the majors.

"Omar is stressing positioning and having a rhythm," said Castellanos, who returned to his natural position after two years of playing outfield in the minors. "The key is keeping your feet moving.

"Wally is a laid-back guy who I really like and have learned a lot from. He's told me, ‘Don't try to be too mechanically perfect.' I'm just trying to be natural up there, and that's loosened me up. I'm just trying to get a good pitch to hit."

His challenge is quite simple: get better every day.  And the Tigers are counting on that.