ADELAIDE: Former U.S. Open champion Marin Cilic recovered from a mid-match wobble to beat American Tommy Paul and reach the semi-finals of the Adelaide International 2 event on Thursday, but Russian Karen Khachanov was knocked out by Frenchman Arthur Rinderknech. Fourth seed Cilic dug deep to seal a 6-4 2-6 6-3 win over the in-form Paul, who had won 12 of his past 14 matches coming into Thursday’s contest. Third seed Khachanov, who was runner-up at the Adelaide International 1 event, suffered a 7-6(7) 7-5 defeat by world number 58 Rinderknech. Croatian Cilic said he was pleased with his performance so far this season, having also reached the semi-finals of the first event in Adelaide last week. “Fantastic start to the year, tough matches,” Cilic said in his on-court interview. “He (Paul) played really well throughout the match and just a couple of points, in the end, decided the difference in the third set.” French qualifier Corentin Moutet secured a 6-4 6-4 win over Brazil’s Thiago Monteiro and will face Rinderknech in the last four. Thanasi Kokkinakis is due to play Aleksandar Vukic in an all-Australian clash later, with the winner set to play Cilic for a spot in the final. In the women’s event, third seed Coco Gauff reached the last four with a 6-3 6-4 victory over Croatia’s Ana Konjuh but American Madison Brengle was forced to retire from her match against Alison Riske due to a slight calf injury. Gauff said she had improved since losing to world number one Ash Barty last week and hoped to build on her performance heading into next week’s Australian Open Grand Slam. “I took a lot of positives from that match and I think I’ve been improving and working on it this week,” the 17-year-old told reporters. “I’m hoping to continue that momentum through the rest of this tournament and through all the Australian Open.” Gauff will play the winner of the match between eighth seed Ludmilla Samsonova and American Madison Keys. Earlier, Brengle retired from the match with the score 3-3 in the first set, sending Riske through to the semi-finals where she will face the winner of the contest between fourth seed Tamara Zidansek and Lauren Davis.