Fifth seeds Paes and Stepanek lost 6-3 6-4 to the second-seeded Bryan brothers in the summit clash yesterday.
Paes was equally complimentary of both his partner and his opponent.
"Even though we got beaten today by one of the greatest teams of all time, my team and Radek's team came out and brought everything they had to this tournament," Paes said.
"I can guarantee you we will be giving it everything we have every single day for the rest of the year," he added.
Paes felt the Bryans produced a magical performance to clinch the title.
"These guys always bring magic to the court," said 39-year-old. "But we put it on the line today and we will come back and keep doing it."
Paes has won two US Open men's doubles title in 2006 (with Martin Damm) and 2009 (with Lukas Dlouhy), as well as a mixed doubles title in 2008 (with Cara Black).
The win was a measure of revenge for the Bryans who lost to Paes-Stepanek in the finals of the Australian Open earlier this year.
"I think they started really well," Stepanek said.
"They were all over our serve from the beginning and making life very difficult for us out there. They were the better team today, so they deserve the win."
The Bryan brothers won their previous US Open titles together in 2005, 2008 and 2010. In addition, Bob has won four US Open mixed doubles title while Mike has one to his name.
The brothers will now head to Spain with the rest of the US Davis Cup team to do battle next weekend against David Ferrer and the rest of the Spanish Cup team in a semifinal tie.
