Paes and his Slovakian partner Daniela Hantuchova, unseeded in the tournament, upset eighth seeds Mahesh Bhupathi and Elena Vesnina of Russia 6-0, 2-6, 10-6 to make it to the quarter-finals of the mixed doubles.
Sania and her Zimbabwean partner Cara Black beat the pair of Eugenie Bouchard of Canada and Russia's Vera Dushevina 6-4, 6-3 in 72 minutes to advance in the women's doubles.
The Indian then joined hands with Romanian partner Horia Tecau to outplay Anastasia Rodionova of Australia and Britain's Colin Fleming 6-2, 6-2 in a 51-minute mixed doubles pre-quarter-final match.
Another Indian, Rohan Bopanna and his partner Katarina Srebotnik of Slovenia also entered the quarter-finals of the mixed doubles after posting 7-6(5), 7-5 victory over the Australian duo of Ashleigh Barty and John Peers.
The mixed doubles pre-quarter-final involving two Indians in Paes and his former partner Bhupathi was an intense affair and lasted 57 minutes.
After winning the opening set comfortably, Paes-Hantuchova slipped in the next one, even as Bhupathi-Elena converted two of the three break-points to run away with the second set.
The third and deciding set was closely fought, but Paes and Hantuchova held their nerves to emerge triumphant.
They will play Kristina Mladenovic of France and Daniel Nestor of Canada in the last eight.
Sixth seeds Sania and Cara hit 23 winners en route to a comfortable women's doubles victory over their unseeded opponents in the third round match. The Indo-Zimbabwean pair converted five out of seven break-points, while their opponents could convert just two out of six.
Sania-Cara now have a tough task as they meet the world No 1 Italian combo of Sara Errani and Roberta Vinci in the quarters.
It was an easy outing for Sania-Tecau in their mixed doubles second round match. The pair won 56 points as compared to just 33 by the Aussie-British pair.
Sixth seeded Sania-Tecau next face the winner of the match between Julia Goerges-Aisam-Ul-Haq Qureshi against Andrea Hlavackova-Max Mirnyi.
Meanwhile, Bopanna and Srebotnik took an hour and 21 minutes to get the better of their unseeded opponents.
The Indo-Slovenian combination failed to convert as many as nine break-points out of 12 they got, but still prevailed over the Australian pair in a hard-fought contest.
Bopanna-Srebotnik take on another Australian duo, Jarmila Gajdosova and Matthew Ebden in their next match.
Image: Katarina Srebotnik of Slovakia and India's Rohan Bopanna at the Australian Open
Photograph: Clive Brunskill/Getty Images
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