Zeller finished with 16 points and five rebounds while Watford supplied 13 and 11 as the Hoosiers (22-3, 10-2 Big Ten) won a second straight following last week's loss to Illinois.
Victor Oladipo helped out Indiana with 13 points and eight boards in the triumph.
Nebraska (12-13, 3-9) was paced by Dylan Talley with 16 points.
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