Federer leads his FedEx ATP Head2Head series with del Potro 15 - 5 ( 10 - 5 on hard court ) .
The Argentine 's lone Grand Slam singles title -- the 2009 US Open -- came with a defeat of the Swiss great in the final .
Federer leads his FedEx ATP Head2Head series with del Potro 15 - 5 ( 10 - 5 on hard court ) but the Argentine 's lone Grand Slam singles title -- the 2009 US Open -- came with a defeat of the Swiss great in the final .