The news of Nadal's withdrawal might have been heartwarming for the French, who registered disappointing results in New York.
The second-set tiebreaker - 31 minutes, 6 seconds long - produced high-intensity drama, featuring seven match points before Andy Murray prevailed.
Nick Kyrgios will now take on Sam Querrey in the semifinals. The other semi sees Rafa Nadal take on Marin Cilic.
Rohan Bopanna and Marcin Matkowski knocked out Romania's Florin Mergea and Serbia's Viktor Troicki 6-3 6-4.
Novak Djokovic advanced to the quarter-finals of Mexico Open after 4-6 6-4 6-4 win over Juan Martin del Potro.
Roger Federer failed to convert three match points in third set and suffered a 6-3 6-7 6-7 loss to Evgeny Donskoy.
Former world number one Maria Sharapova makes her return to the circuit in Stuttgart in April after completing a 15-month ban for doping.
Clay-court circuit lost a major event several years ago when the Mexican Open in Acapulco switched to hardcourts.
Novak Djokovic said he feels in a healthier frame of mind since his travails of recent months after his second exit from after Australian Open.
Andy Murray looked in good shape during a 6-4, 6-1 first round win over Malik Jaziri at the Dubai Tennis Championships.
Novak Djokovic played his first tournament since he suffered an unexpected loss to Denis Istomin at Australian Open.
Both Roger Federer and Andy Murray are playing their first tournament in Dubai since the Australian Open where they had contrast results.