Carlos Alcaraz kept alive his hopes of reaching the last four of the ATP Finals with Wednesday's 7-5, 6-2 win over an emotionally fraught Andrey Rublev.
World number two Alcaraz has struggled with form and fitness over the past few months and was staring at possible early elimination after losing his first Red Group match with Alexander Zverev.
But the 20-year-old comfortably dealt with Russian Rublev who once again failed to make his mark in a big match with one of tennis' leading lights, a problem which has dogged his career.
Fifth seed Rublev, the reigning Monte Carlo Masters champion, was on the verge of tears after losing his opener with Daniil Medvedev and lost control again after giving away a service game at the start of the second set.
Being one set and a break down was too much for the 26-year-old who started smashing his racket into his own knee, drawing blood as he sat down.
Troubled Rublev was still bleeding down his leg after the change of court and, just as against Medvedev, gave into his anger and promptly collapsed.
After throwing away his serve to love in game seven to give Alcaraz the chance to serve for the match Rublev sat with his towel over his head, clearly trying to hold back the tears before Alcaraz sealed a straight-sets victory.
Alcaraz will now face Medvedev in his final match with his Russian opponent having a chance to reach the semi-finals ahead of his clash with Zverev.
World number three Medvedev can book an early place in the next round if he wins in straight sets, while Alcaraz's victory means seventh seed Zverev will be through with a win of any sort.
td/bsp