Katie Boulter overcame a tie-break mix-up to claim one of the best victories of her career in the first round of the Australian Open.

A change in the rules for this tournament means matches that reach 6-6 in the deciding set will be finished by a first-to-10-points tie-break rather than the standard first-to-seven-points one.

Although the umpire reminded players and fans when the score reached 6-6 in the third set against Ekaterina Makarova, Boulter was so focused she did not pay attention and celebrated exuberantly when she reached 7-4.

She walked to the net only to realise her mistake but reacted impressively to win 6-0 4-6 7-6 (6) after two hours and 24 minutes in oppressive Melbourne heat.

The 22-year-old from Leicestershire said: "I was in the moment and I kind of forgot it was first to 10 but I'm happy I could dig deep and get through it in the end.

"I ended up getting the win, I'd probably have been really devastated had I not. I can laugh it off now. At least I know the rule so it definitely won't happen again."

Boulter lost the next two points but then won three in a row to become the first British player through to the second round.

She said: "I think it's actually very tough, because you've just released and you think you've won the match, to get back to work and find a way. I thought I did that really well and I'm pretty proud of myself for digging deep."

This was a match that showed how far Boulter has come over the last year, climbing 100 spots in the rankings and beginning to establish herself as a genuine threat to higher-ranked opponents.

Makarova is a two-time grand slam semi-finalist, including here four years ago, and can boast 13 wins over top-10 players at the slams but Boulter crashed 53 winners past her and her mental strength was just as impressive as her shots.

Boulter would have to cause a huge upset to make it further, though, with 11th seed Aryna Sabalenka, who has been hotly tipped to challenge for the title, next up.