The Pole, who took the title in 2025 with an astonishing 6-0 6-0 demolition of Amanda Anisimova, has been playing down her chances of a successful defence, having lost her only grass-court match this season in Germany following a fourth-round exit at the French Open.
But though she certainly looked far from the form that enabled her to win her last 20 games en route to the title last year, the six-time grand slam champ was at least happy with the way she produced her best when it was most needed in the third set as she prevailed 6-1 2-6 6-3 in just over two hours.
"It was a tough couple of weeks and not a season where everything went how I wanted," Swiatek said in her on-court interview, having earlier looked close to tears.
"Just happy to be here, happy that I could get through a match like that, because I got quite tense in the second set and then I was able to come back to my game.
Taking to the court for the traditional Tuesday Centre Court opening match for the women's champion, it all started swimmingly for the 25-year-old as she swept six games on the bounce after losing the opening game.
Having won the last three sets she played last year by 6-0 scorelines, two against Anisimova and the last set of the semi-final against Belinda Bencic, it meant Swiatek had taken 26 of the last 27 games she'd played on Centre Court.
But things started to unravel in the second stanza against the wily 30-year-old Townsend, who's previously made history as the first mother to grab the world No.1 ranking in doubles, as she used her serve-and-volleying skills to disrupt the Pole's rhythm.
The key to the third set may well have been the marathon first game which dragged for over 20 minutes and featured nine deuces before Swiatek saved a fourth break point and went on a precious hold.
Swiatek managed to pull away, making the decisive break for a 5-3 lead before serving out the match.
In the second round she plays Karolina Pliskova, who was defeated by Ash Barty in the 2021 final and who's on the comeback trail after missing nearly all the 2025 season following two operations on her left ankle..
Earlier, Anisimova returned to Wimbledon for the first time since her horror final and found release with a 6-3 6-2 win over North Macedonia's Lina Gjorcheska, while Elena Rybakina, the 2022 champion, survived a tough examination from last year's French Open sensation Lois Boisson to prevail 6-4 1-6 6-3.
Kazakh Rybakina will take the world No.1 spot for the first time if she can go on to regain the title.Â
The 2024 Wimbledon finalist Jasmine Paolini, the 13th seed, battled back after a nightmare opening to beat American world No.195 Robin Montgomery 0-6 6-4 7-5.