Swiss Jil Teichmann became the first player into the Adelaide International semifinals today after a marathon win over Latvian Anastasija Sevastova.

Teichmann, 23, had to do it th hard way, eventually winning 6-4 6-7 (8-10) 7-5.

Jil Teichmann had to battle to reach the semi-finals. Photo: Tennis Australia/ DAVID MARIUZ

After winning the opening set Teichmann had five match points in the second-set tiebreaker but eventually lost.

And then trailing 5-4 in the third she was forced to save two match points before levelling and breaking Sevastova’s serve.

“It was a rollercoaster and what I felt was nerves,” Teichmann said.

Anastasija Sevastova of Latvia reacts against Jil Teichmann at the Adelaide International. Photo: Tennis Australia/ JAMES ELSBY

“It was a very tense match, very long rallies every time and Anastasija is a tough player and you have to play every point and every game, doesn’t matter if you’re serving or returning.”

Teichmann will face the winner of the clash between American Danielle Collins and French Open champion Iga Swiatek of Poland.