Diego Schwartzman beat Grigor Dimitrov 3-1 at the Ultimate Tennis Showdown on Monday night.
The Argentine was on the back foot in the first set when Dimitrov took him to 14-13, meaning his opponent had it all to do.
Schwartzman, 28, then came back against the 30-year-old Bulgarian when he took an equalising set at 12-10.
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He then really hit his stride and with much better consistency - 16 unforced errors to his beaten opponent’s 22 - scored an impressive 17-9 to go ahead for the first time in the match.
Schwartzman then secured the win when he rounded out the win 15-10.
UTS: Moutet wins against Medvedev
Earlier in the day Schwartzman secured a whitewash 3-0 win over Alexander Bublik. Dimitrov was in action earlier in the day's play, losing 3-1 again, this time to Chilean Cristian Garin.
Corentin Moutet won the day's first match, 3-1 against Taylor Fritz.
Fabio Fognini crashed 3-0 to Russia's Daniil Medvedev, and then lost by the same scoreline as he faced Fritz, falling 12-2 in a dreadful second-set showing.
Medvedev took to the court again in the evening match against Moutet. The Frenchman secured a 3-1 win over his Russian opponent. Medvedev looked to be cruising to a victory as he won the first set 18-11.
At that point Moutet launched a comeback, securing three consecutive sets 16-13, 16-10 and 18-10.
In the last match of the day, four aces was not enough for Bublik as Garin defeated him 3-0.
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