NEW YORK (AP)  -- First he got the sheepskin. Then came the summons.

Police say a New York University student has been ticketed on a trespassing charge after he burst onto the field at Yankee Stadium during his graduation and darted through the diamond in his academic gown and underwear.

William Lopez tagged third base and was making for home plate when a security guard tackled him during Wednesday's ceremony. Students had been told to stay off the storied field.

The 21-year-old film major tells the Daily News he did it out of "happiness and spontaneity." But NYU spokesman John Beckman calls the stunt disappointing, saying the university expects students to abide by rules.

Lopez has been released until a July 14 court date.

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