World No. 1 Ashleigh Barty was five points away from losing her first match of the season against Coco Gauff in Adelaide three weeks ago, trailing a set and a break at 6-4, 4-2—and facing another break point to go down a set and a double break—before coming back to win that one in three sets, 4-6, 7-5, 6-1.

It turns out that the American teenager is the only player who’s come anywhere close to beating Barty this year, as she hasn’t dropped a set since—she hasn’t even been pushed past 6-4 in any set since the middle set of that match.

4-6, 7-5, 6-1 (Gauff in Adelaide 2nd Rd)
6-3, 6-4 (Kenin in Adelaide QFs)
6-2, 6-4 (Swiatek in Adelaide SFs)
6-3, 6-2 (Rybakina in Adelaide F)
6-0, 6-1 (Tsurenko in Australian Open 1st Rd)
6-1, 6-1 (Bronzetti in Australian Open 2nd Rd)
6-2, 6-3 (Giorgi in Australian Open 3rd Rd)
6-4, 6-3 (Anisimova in Australian Open 4th Rd)
6-2, 6-0 (Pegula in Australian Open QFs)
6-1, 6-3 (Keys in Australian Open SFs)

One of the keys to Barty’s success this year has been her serve—she’s held 46 of her 47 service games during the Australian Open fortnight and 81 of her last 82 overall, a stretch that dates back to that 6-4, 4-2 game against Gauff in Adelaide, where she fought off break point and held to close the deficit to 6-4, 5-3.

Barty and her 10-match, 20-set winning streak will take on big-hitting American Danielle Collins for the Australian Open title on Saturday.