'Pride and pressure' keep Andy Murray alive in Olympic doubles
The former world number one and three-time Grand Slam title winner teamed up with Evans and clinched a 2-6, 7-6, 11-9 win over Japan's Taro Daniel and Kei Nishikori.
The British duo were 9-4 down in the final-set tiebreaker but were aided when Nishikori served a double fault on one of the match points, as the tension was cranked up on Court Suzanne Lenglen.
Murray, a two-time singles gold medalist at the Olympics in 2012 and 2016, will retire from the sport once his Olympics is over.
"I felt fine this morning. I was a bit nervous but I didn't feel terrible," said Murray as he looked back on what could have been his final day as a tennis player.
"As the match started I was feeling it a bit, I was aware of the situation but I still have some pride, I want to perform well.
"There is always pressure playing for your country at the Olympics. You want that pressure and if I didn't feel that, then I shouldn't be here."
Murray's exploits down the years included famously ending Britain's 77-year wait for a men's champion at Wimbledon when he triumphed in 2013.
However, he has been ravaged by injuries in recent years, slumping to 121st in the world. He pulled out of singles in Paris.
The Scot has played with a metal hip since 2019 and suffered ankle damage earlier this year before undergoing surgery to remove a spinal cyst, which ruled him out of singles at Wimbledon.
He described Sunday's typically gutsy performance as "up there" with his best trademark fightbacks.
"The body doesn't feel amazing. I haven't played much tennis in the last few months," he said.
"But I have turned around a lot of matches that I looked unlikely to win. I have always had that mental toughness and strength.
"I've come from two sets down more than anyone else but I couldn't have done it on my own today."
Evans said that he may pull out of his singles clash against Tunisia's Moez Echargui on Monday to preserve energy for his partnership with Murray.
"Our best medal chance is not me in singles," said Evans.
"I'm immensely proud to be on court with Andy but he'll tell you that he's here to win. He's not thinking about his retirement," he said.