Tomic admits he's 'not the smartest' after U.S. Open flop

NEW YORK (Reuters) - Australian Bernard Tomic admitted he is "not the smartest person in the world" after exiting the U.S. Open in the first round on Monday with a 3-6 6-3 6-4 6-4 defeat to Gilles Muller that could send him tumbling out of the top 150.