Rafter, the two-time US Open champion, revealed the friction between the pair when speaking publicly about his wishes to see Barty return to the sport.

Barty shocked the world in March when she announced her retirement at the age of 25, having won Wimbledon in 2021 and the Aussie Open this year.

Her Aussie Open final triumph against Collins was a heated affair and Rafter says he could sense the pair did not get on.

“I knew with her and Danielle, they had a bit of a … what’s the word – there was no love lost anyway,” Rafter said, according to The Herald Sun.

“Danielle’s pretty feisty. And Ash didn’t want to lose to her.”

The pair played five times with Barty winning four times. However, Collins won their previous meeting heading into the Aussie Open this year.

Barty’s body language also showed plenty of signs she was desperate to defeat Collins for personal reasons.

Barty was down a double break in the second set — and the match looked certain to head into a decider — but the former world No. 1 showed raw courage to fight back and take the second set in a tiebreaker.

She let out an enormous roar on match point after securing the 6-3 7-6 (7-3) victory.

The match had earlier taken a sudden twist in the second set when Collins was fired up by the Aussie crowd cheering against her.

She had Barty visibly frustrated when secured a double break.

Barty was motioning to her players box during a change of ends and was waving her hands around with an angry expression on her face.

It is something the tennis world almost never got to see towards the end of the Queenslander’s career.

“It was pretty funny, I don’t know how much you can pick up on the on-court subtleties of it but I’m pretty aware of Ash and I understand where her mind’s at and I can see all her little movements and ticks,” Rafter said of Barty’s surprisingly raw emotion.

“I was going, ‘oh no, she’s getting rattled, she’s not good’.

“But she was able to pull it out which was pretty important.

“I would have hated to see her get to the final and lose because she was the dominant player. I like seeing the best players win.”

There was also a moment of friction inside the bowels of Rod Laver Arena in the final moments before the pair stepped out onto the court for the final.

Behind the scenes cameras captured the moment Collins appeared to ignore Barty as they walked towards each other. The pair did not stop as they passed each other and Collins did not even change direction.

Channel 9 presenter James Bracey light-heartedly suggested Collins had snubbed Barty’s greeting.

“I reckon Ash went for the ‘hello’ and she (Collins) has given it the straight 180,” he said.

Rafter, meanwhile, just wants to see Barty back playing tennis, despite admitting there seems little hope she would feel the competitive fires drive her back to the sport.