Bairstow hit an unbeaten 54 from 67 balls to help England recover from 83-5 to 171-5 on the opening day against Sri Lanka.
Hales top-scored with an undefeated 71, but first and foremost paid tribute to Bairstow.
“The way that Jonny came in and counter-attacked was brilliant on what I thought was a tricky pitch,” said Hales.
“To do it on a wicket like that was pretty tough work, and he made it seem like nothing.
“It shows how much he’s come on in the last year as a Test cricketer, and he looks the real deal. He looks a lot more confident.
“A couple of years ago, the West Indians were bouncing him quite a lot and he looks like he’s brilliant off the back and front foot now, and I guess it’s just a confidence thing.”
Hales and Bairstow added 88 for the sixth-wicket in 21 overs after England slipped from 49-0.
Alastair Cook scored 16 of the 36 he needs to become the first Englishman to 10,000 Test runs before becoming debutant Dasun Shanaka’s first of three wickets in eight balls shortly before lunch.
Shanaka also removed Nick Compton for a third-ball duck and Yorkshire’s Joe Root for a seventh-ball duck. But Hales stood firm, vindicating the selectors’ faith after they stuck by him after a tough tour of South Africa.
“Throughout the Test series in South Africa, I didn’t feel out of my depth,” said Hales, who hit 136 runs in the four Tests.
“It was me making mistakes rather than bowlers necessarily getting me out.
“I’d rather it was that way round, and that it was up to me to correct a few things.
“It’s still a work in progress, but I feel confident.”
Hales took time off at the start of the Championship season, potentially allowing others – including Yorkshire’s Adam Lyth – to steal a march.
He insisted he was given no assurances regarding his Test place. “They (the selectors) didn’t give me any inkling either way,” he said.
“I took a couple of weeks off to recharge myself, and I think that’s done me the world of good.
“It’s proved to be the right decision, and I feel refreshed.
“I knew that top-order players would get runs at the start of the year, and I’m pleased the selectors stuck with me.”
Day one report and analysis: Page 25.