The emotions Juan Martin del Potro showed in his Delray Beach comeback revealed just how moving the match was for the former world No. 4.

Surviving a total of four wrist surgeries, del Potro has returned with a limited backhand and unlimited gratitude for the game and his fans.

Talking to Blair Henley after his opening-round win over Denis Kudla, del Potro thanks fans directly for their support and delivers a promise.

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"I promise I will keep working to play even better than I did today," Del Potro tells the crowd.