#4 Alexander Zverev
The 20-year-old German, Alexander Zverev does not have much to boast of in this season. A powerhouse of talent, Zverev often falters when it matters the most. Yet to learn to keep his calm, Zverev is searching for his best tennis from his last year's performances.
His best so far in this season is a semi-final finish in Acapulco at the Mexican Open where Juan Martin Del Potro produced a flawless performance to school the German in straight sets.
Pulling down David Ferrer in the opening round in Rotterdam was commendable on the part of Zverev only to go down to Seppi in the Round of 16.
There is little room given his recent form for the World No 5 to land a significant result in California whatsoever. Challenging the great Federer is almost a distant dream to have, if at all.
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