GLENDALE, Ariz. -- Corey Seager has done nothing this spring to indicate he isn't pounding on the door of a major-league opportunity more than a month before his 21st birthday.In 11 Cactus League games, Seager has a .500 on-base percentage and has carried himself with the calm and confidence of a 10-year major-league veteran, even teaming with reigning MVP Clayton Kershaw to form a top-seeded doubles team in the club's annual table-tennis tournament.