The fourth seeds are attempting to reach a second consecutive final at Flushing Meadows but have had a rather tough time thus far, with their last three matches all ending in three sets.
The Indo- Czech duo will take on the defending champions Bryan brothers (Mike and Bob) in the semis. Both teams have maintained a tight head-to-head career record with the Bryans leading 4-3 overall. However, they are tied at 3-3 since last year and are yet to meet this year.
The world number one pair is looking to win a Calendar Slam after completing a Career Golden Slam and winning a Non-Calendar Slam. They will finish the year as the top ranked doubles team and are so far the only team to qualify for the year end championships.
Paes and Stepanek only teamed up since the grass court season this year. Stepanek was forced give some tournaments a miss earlier this year due to a set of niggling injuries. But their reunion has come at the right time and their results have been extremely encouraging.
They had earlier reached the Wimbledon semi-finals and are currently ranked 22 in the race to London. Their performance in the last Grand Slam of the year, however, will surely add to their chances to finish among the top eight for the ATP World Tour Finals.
Meanwhile, Sania Mirza and partner Zheng Jie will face Wimbledon champions Peng Shuai and Hsieh Su-Wei in the quarterfinals later today at the Louis Armstrong stadium, in what will be their first meeting.
If Mirza manages to reach the semis, it will be her first since the 2012 Australian Open.