Iga Swiatek survived a scare to start her Wimbledon title defence with a 6-1, 2-6, 6-3 win over American world number 79 Taylor Townsend on Tuesday.
Swiatek suffered a second-set wobble that left her in danger of becoming only the third reigning female Wimbledon champion to lose in the first round in the Open era.
But world No 3 Swiatek, a six-time Grand Slam champion, steadied her nerves in the deciding set, surviving a 21-minute first game before securing the breaks of serve that edged her into the second round.
The visibly emotional Swiatek buried her head in a towel after converting match point.
The 25-year-old Pole hasn't reached the semifinals of a Grand Slam in her last three attempts since winning Wimbledon.
Townsend's power-hitting pushed Swiatek to the brink of another disappointment at the majors.
But the 30-year-old has never been past the Wimbledon second round and Swiatek did just enough to set up a last-64 clash against 2021 Wimbledon runner-up Karolina Pliskova.
"It was a tough couple of weeks. A season when not everything went how I wanted. I don't think I won any three-set matches this year, so I'm happy I could do it," Swiatek said.
"Obviously, it means a lot to be the defending champion here. In the end I kept my composure. I knew I needed to be solid."