John Isner held firm in the face of a late Rinky Hijikata comeback Monday to kick-start his 2023 campaign at the Mifel Tennis Open by Telcel Oppo with a 6-2, 7-6(4) victory in Los Cabos.

The big-serving Isner led Hijikata 6-2, 5-3 at the hard-court ATP 250 before the Australian ramped up the pressure by forcing a second-set tie-break in the pair’s maiden Lexus ATP Head2Head clash. Hijikata then forged an immediate 3/0 lead to boost his chances of forcing a deciding set on the Mexican Pacific coast, but Isner claimed seven of the final eight points to pull through in one hour and 54 minutes.

“It’s a lot of relief. I felt like the match could have been a little bit easier at the end, but my opponent started to play a bit better,” said Isner in his on-court interview. “He made me play and I got a little tight. That’s what happens in tennis. I’m happy to win.”

It was a 350th tour-level hard-court victory for Isner, who hit 31 winners, including 19 aces. Now 8-11 for the 2023 season, the 16-time tour-level titlist will next face top seed Stefanos Tsitsipas at an event where he reached the semi-finals in 2021.

“We have played each other a bunch,” said Isner, when asked about the Tsitsipas clash. “I think I won the first couple of times and he’s won the last five, so I’m going to try to turn that around.

“He’s an incredible player, obviously. You don’t get to No. 3 in the world without being really good, so it’s going to be a big challenge. I will definitely have to play my best, because if I don’t I have no chance of winning.”

Isner’s countryman Aleksandar Kovacevic also sealed a straight-sets win Monday. The World No. 129 beat qualifier Omni Kumar 6-2, 7-5 to set a meeting with second seed Cameron Norrie. Third seed Tommy Paul’s opening opponent will be Felipe Meligeni Alves, after the Brazilian moved past Alejandro Tabilo 6-2, 6-4.