The annual event, which precedes the All-Star Game, will crown a new champion at Busch Stadium in St. Louis.
"I'd love to sit there and watch just as a fan," Morneau said on the team's Web site this week.
The American League's 2006 American League MVP made the decision shortly after he won AL Player of the Week honors.
Last year at Yankee Stadium in New York, he was beaten in the first round by Texas Rangers outfielder Josh Hamilton, but won the event 5-3 in the finals after Hamilton appeared to have become arm weary.
"I told (Morneau) if he wants an excuse, I'll be his excuse," Manager Ron Gardenhire sarcastically told the St. Paul Pioneer Press Tuesday.
Morneau is batting .318 to date with 21 homers and 69 RBI and will be an AL all-star.
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