"I was just trying to hang on in my service games through the first set and just stay only one break down,” said Hewitt.
"In the end it worked perfectly because I was able to draw a couple double faults out of him and obviously got that break and then broke again at 6-5. Once I won the first set, I felt like I was really in control."
Jeremy Chardy emerged victorious from an all-French contest with Nicolas Mahut 7-5 6-7 6-3 while home wildcard Samuel Groth held his nerve in consecutive tie-breaks to move into the last eight with a 4-6 7-6 7-6 win over Pierre-Hugues Herbert.
At the Chennai Open, wildcard Yuki Bhambri became the first Indian player to reach a quarter-final of an ATP tour event since 2009 when his opponent, third seed Fabio Fognini, retired with a quadriceps injury. Bhambri was leading 6-1 5-5 at the time and will now face Canada’s Vasek Pospisil who beat Yen-Hsun Lu without hitting a ball after his opponent withdrew.
Seeded duo Benoit Paire and Marcel Granollers both won in straight sets to set up an intriguing last eight meeting.
Results - Qatar Open
Gael Monfils beat Daniel Brands 6-2 6-1
Florian Mayer beat Victor Hanescu 6-4 6-7(8) 6-4
1-Rafa Nadal beat 7-Ernests Gulbis 7-5 6-4
Peter Gojowczyk beat Dustin Brown 6-3 3-6 7-6(5)
Results - Chennai Open
4-Benoit Paire beat Guillermo Garcia-Lopez 6-1 6-4
6-Marcel Granollers beat Ramkumar Ramanathan 6-2 6-4
5-Vasek Pospisil beat Lu Yen-Hsun WO