Cape Town - South Africa's Lloyd Harris has recorded the biggest win of his career, beating France's Gael Monfils in the first round of the ATP Tour's Chengdu Open in China in Tuesday.

Harris, 21, ranked 129th in the world, won 3-6, 6-2, 6-1 against Monfils, who was the fifth-seed at the tournament.

Monfils is currently 38th in the latest rankings.

Harris now boasts a 10-6 record on the ATP Tour and will look to improve on that when he faces Australian qualifier Bernard Tomic in the second round.

Last month Harris qualified for his maiden Grand Slam at the US Open at Flushing Meadows, but was beaten in the first round by France's Gilles Simon.

Results of Tuesday's ATP Chengdu Open matches at the Sichuan International Tennis Centre (x denotes seed): 

First round

Ruben Bemelmans (BEL) bt Mischa Zverev (GER) 6-3, 2-0 (retired)

Matthew Ebden (AUS x6) bt Evgeny Donskoy (RUS) 6-3, 6-4

Sam Querrey (USA) bt Guido Pella (ARG) 7-6 (8/6), 6-1

Taylor Fritz (USA) bt Chun Hsin Tseng (TPE) 3-6, 6-3, 6-4

Vasek Pospisil (CAN) bt Radu Albot (MDA) 6-3, 6-4

Felix Auger-Aliassime (CAN) bt Yibing Wu (CHN) 6-3, 6-7 (2/7), 6-1

Mikhail Kukushkin (KAZ) bt Tennys Sandgren (USA x8) 6-4, 6-3

Lloyd Harris (RSA) bt Gael Monfils (FRA x5) 3-6, 6-2, 6-1