Del Potro recorded just his seventh victory over Federer in a pulsating final at Indian Wells at the weekend.
Both players could be seen getting irate at some points during the match as they traded blows.
Federer at one point aimed some barbed comments towards the umpire for a call he thought was out, only for hawkeye to prove the decision was correct.
And Del Potro also remonstrated with the official for not controlling the noisy crowd at times.