The day's opening game saw Elliot Benchetrit beat German Dustin Brown 3-1, in the first of five exhibition games, giving the Frenchan the chance to progress to the next round.
Greece's Tsitsipas beat Moutet 3-2 in the Ultimate Tennis Showdown event.
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Stefanos Tsitsipas won his match against France's Corenttin Moutet in a close-run 3-2 win. The defeat means that Moutet is no longer in contention for the semi-finals.
At the other end of the scale, Alexei Popyrin was crushed 4-0 by Matteo Berrettini.
Feliciano Lopez fell to a narrow defeat when Richard Gasquet edged him 3-2, with the French athlete confirmed for the semi-finals.
In the day's final game, Benoit Paire lost 3-1 against Belgium's David Goffin.
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