Aryna Sabalenka raged at coach Anton Dubrov before watching him walk out in the middle of her match.The world No.1 was visibly frustrated during her second round-robin match against Jessica Pegula at the season-ending WTA Finals.Sabalenka admitted she lost her coolGettyDuring the closely-fought contest, Sabalenka was seen airing her feelings towards her box where Dubrov was sitting.Her offloading appeared to be too much to bear for Dubrox who left his seat during the third set.However, his sharp exit didn’t appear to throw the US Open champion off course as he went on to claim a 6-4, 2-6, 6-3 victory.The win means the Belarusian still has a chance to make it out of the group stage and qualify for the semi-finals of the event.Crossed the lineSabalenka later conceded that she was highly stressed during the match and was probably too harsh on her coach.“Maybe I went a little bit too much on Anton, we’re going to probably – if he’s still here – we’re going to talk, but I don’t know where he is,” Sabalenka told The Tennis Channel.“But yeah, I went a bit too much. I was so frustrated inside of me and I was just trying to let it go, probably I went too far – not probably – I went too far.”Although the four-time Grand Slam winner admitted she had crossed the line, she believes her coach made the right decision in leaving her to it.“Honestly, I think it was the right move from him to probably just let me be on my own,” she added.“I don’t want to say it the way I wanted to say, but he really upset me and I was really stressed and angry on him, and it really helped me to pull out such tennis.”Sabalenka insists there are no hard feelings after Dubrov left the matchGettySabalenka came into the match on the back of a victory over Jasmine Paolini in her first match of the week.Chance of redemptionShe now faces American Coco Gauff in their final round-robin match in what will be a repeat of the French Open final.Gauff was victorious at Roland Garros, coming from a set down to win but the final was remembered for Sabalenka’s post-match comments where she claimed Gauff only won because she took advantage of her unforced errors and that Iga Siwatek would have beaten the American.Ahead of Wimbledon this summer, Sabalenka released a statement and a written apology to Gauff.“I’ve always been really good with Coco,” Sabalenka said.“I didn’t really want to offend her. I was just completely upset with myself, and emotions got over me. I just completely lost it.It’s a familiar foe up next for SabalenkaGetty“I did what I did. I get what I deserve, I believe. It was a tough time for me. The lesson is learned.“This time the emotions took over me. In the finals or semi-finals, sometimes I can get over-emotional. I would like to improve that.“I would like to stay to the same mentality I have during the tournament, because I believe I get over-emotional at the last stages of the tournaments because I have this desire of winning.”