Early on Hingis and Paes, who received two walkovers en route to the final, looked like they would be in for an easy afternoon's work. They got their noses in front as early as the third game, Hingis firing a forehand winner to break Mattek-Sands' serve to love.
Despite playing two Americans, there was no shortage of support for the No.4 seeds from the Louis Armstrong crowd, who roared their approval when Hingis swatted away a trademark two-fisted volley to wrap up the opening set.
They ratcheted the pressure up a notch at the start of the second and the home favorites responded superbly, fending off a couple of break points before carving out one of their own when Mattek-Sands expertly dug out a backhand volley. Another moment of brilliance gave them the break and also the momentum.
As in the first set, a solitary break proved enough in the second, Querrey calmly serving out to force the deciding match tie-break.
For a brief moment it looked like they would complete the turnaround. Hingis was the first to blink in the tie-break, dropping both points on her serve - sending a tight drive volley long on the second - to slip 4-1 behind. However, they were not trailing for long, Querrey double faulted to surrender the advantage and when Paes punched a return onto the sideline the finishing line loomed into view.
A couple of crushing blows from the Indian later and they were across it, a 6-4, 3-6, 10-7 victory giving them a third Grand Slam mixed title together.
"It's incredible. I mean I'm so lucky and fortunate to have Lea as a partner on my side - I know he has my back all day long," Hingis said. "If I don't come up with a return but 10 double faults, he's still there with me!
"It's amazing the understanding we have for the game, and for each other, how we cover the court at the net, baseline, whatever works. Even one thing doesn't work we come with plan B or C like it was today."