Katie Boulter overcame issues with her serve to edge past Beatriz Haddad Maia 6-4 6-4 in the opening round of the Merida Open.
The British No 3 landed only 36 per cent of her first serves against her out-of-form opponent, who has now lost six of her seven matches in 2026.
By contrast, Boulter won her most recent tournament at the Ostrava Open, but still looked out-of-sorts in Mexico as she made 38 unforced errors and had her serve broken five times in a contest which lasted almost two hours.
The first four games of the match went against serve before Haddad Maia eventually held, although it was Boulter, who held in the sixth and 10th games to take the opening set.
The 29-year-old broke twice more to race into a 3-0 lead in the second but experienced more problems with her own serve, eventually taking a second match point after hitting a ninth double fault on the first.
"I just tried to keep believing in what I'd been doing," Boulter said.
"Obviously very different conditions from what I've been playing in recently and I just had to adjust and keep fighting.
"I've had many battles with Bea and she's an incredible player and she never gives you anything so it was a long match... I'm pleased I got through that."
Cameron Norrie's Abierto Mexicano Telcel campaign lasted just 56 minutes as he lost 6-3 6-2 to Spanish teenager Rafael Jodar.
A tight first set was decided when Jodar took a second break point in the eighth game to lead 5-3 then served out the opener.
A whirlwind second set was anything but competitive as Jodar, a former junior US Open champion, reeled off five games in a row - a run during which he lost only two points.
