The Argentinean broke the winning streak of Federer with a 3-6, 7-6 (5), 4-6, 7-6 (4), 6-2 victory on Monday, Sep 15 to lift his first ever Grand Slam title .
Federer who has till now won five straight US Open titles said, "Maybe I look back and have some regrets about it."
"But, you know, you can"t have them all and can"t always play your best," he added.
The 20-year-old, sixth seeded Argentinean failed to beat the Federer in their six previous encounters. And Federer has never been beaten by anyone other than Rafael Nadal in a major final.
Potro not only scripted history by beating Federer, he kept the Tennis legend from breaking the record of Bill Tilden by winning the US title six times in a row.