Nick Castellanos, Tigers
Credit: Mark Cunningham / MLB Photos / Getty Images

When a team trades a guy like Prince Fielder – the son of a franchise hero and an intimidating lineup presence – to make room for you, you better pay that off. That's the challenge facing 22-year-old Castellanos, who comes into Tigers big-league camp this season as the everyday third baseman. Last year, he was relegated to minor league camp halfway through March, so keep an eye on his numbers from March 15 onward, when he starts facing major league pitchers.