The former world number one, who won back-to-back titles Qatar Open in 2012 and 2013, was down 0-4 in the third set and saved a match point at 5-4 in the decider before eventually prevailing after two hours and 48 minutes.

It is not the first time that Azarenka has come back from the brink of defeat against Putintseva.

In the pair's only prior encounter, Azarenka had to save two match points before ousting the world number 42 at the Grampians Trophy in Melbourne.

Azarenka now has a career win-loss record in Doha of 18-2 as she aims to become the first three-time Qatar Open champion.

She will face Madison Brengle in the second round after the American defeated Turkish wildcard İpek Öz 7-5, 6-3.

Elsewhere in the capital, Danish teenager Clara Tauson upset Tokyo 2020 gold medallist Belinda Bencic 6-4, 3-6, 6-3 in her tournament debut.

In the Dane's first main-draw match at a Women's Tennis Association 1000 event, Tausen shocked the Swiss star in under two hours.

"It was a very tough match," said Tauson.

"I know Belinda is playing very well so I had to play my best today, and I did sometimes.

"I have my confidence but every match is really tough at this level, so I'm doing my best."

The world number 33 lost just four points on her serve in the final set, with the decisive break against Bencic coming in the fourth game.

Tauson won 12 of the 13 points played in her last three service games to complete the upset.

Tauson is due to meet Spain's third seed Paula Badosa in the second round.

The only other seeded player in action today was number nine Jessica Pegula of the United States who dispatched the Czech Republic's Kateřina Siniaková 6-3, 6-2.

Spain's Garbiñe Muguruza headlines tomorrow's fixtures as she takes on Sorana Cîrstea in the round of 32 after the Romanian beat Egypt's Mayar Sherif 6-2, 6-1.