Top seed Andrey Rublev has crushed a demoralised Borna Coric to reach the final of the Next Gen ATP Finals.
Russian No.1 Rublev, ranked 37th in the world, dominated his fellow 20-year-old with his superior power to win 4-1 4-3 (8-6) 4-1 in little over an hour.
Coric, who perhaps regretted battling back to win his final round-robin match in five sets despite already having qualified, looked jaded and took his frustration out on his racket.
Twice he broke frames in the third set as Rublev raced away to victory and a final against either Chung Hyeon or fellow Russian Daniil Medvedev who are in action later.
Coric was too passive in the first set but revived in the second after coach Christian Schneider told his player, through headphones, to "give me more energy".
The Croatian got himself into a tiebreak but a misguided forehand at 6-6 gave Rublev a second set point and he made no mistake.
One of the many innovations at the Next Gen Finals, the headphone exchanges between coach and player make for interesting listening for the crowd and TV audiences and Coric's reaction to losing the second set was candid.
"I don't know what to do anymore," he said.
Coric even became irate with one live Hawkeye call - the system that has replaced human line judges at the event.
Rublev was thrashed by South Korean Chung in the round-robin phase but claimed his spot in the semi-finals with victory over Canadian teenager Denis Shapovalov on Thursday.
Chung, like Coric, was undefeated in group play.
