Andrey Rublev was defaulted from his semifinal at the Dubai Championships for yelling in the face of a line judge, allowing Alexander Bublik to advance to the final on Friday.
The second-seeded Rublev erupted after Bublik won a point to take a 6-5 lead in the deciding set.
The Russian, who is ranked No. 5, immediately pointed to the baseline, walked to the line judge, leaned over and shouted in his face.
ATP supervisor Roland Herfel came to the court accompanied by a Russian speaker, who said Rublev swore in his native language.
Rublev responded: “I was talking to him in English.” He insisted he did not use the profanity.
But umpire Miriam Bley defaulted Rublev for unsportsmanlike conduct, after which the seventh-seeded Bublik said “I'm OK to continue” with the match.
Bublik won 6-7 (4), 7-6 (5), 6-5.
Later, defending champion Daniil Medvedev faced Ugo Humbert in the other semifinal.
Rublev won the hard-court tournament in 2022 but lost to Medvedev in last year's final.
The big-serving Bublik is looking for the fifth singles title of his career. The Kazakh player won the Open Sud de France in Montpellier last month.