Former world number six Gael Monfils' return to the ATP Tour ended with a straight-sets first-round defeat to Jordan Thompson at the Indian Wells Open on Wednesday.

The 37-year-old Frenchman has not played competitively since August last year due to injury but was eliminated by Thompson 6-3 6-1 in one hour and five minutes.

The Australian was ruthless, converting four of six break points generated, while he did not offer up any to Monfils.

Monfils was rusty, committing 17 unforced errors to Thompson's five, but the veteran hit 14 winners.

Thompson's victory earns him a second-round meeting with second seed Stefanos Tsitsipas.

Brandon Nakashima won the battle of the Americans, getting past John Isner 7-6 (9-7) 6-3 in one hour and 39 minutes. Nakashima progresses to face fifth seed Daniil Medvedev.

China's Wu Yibing produced some thrilling tennis, including an astonishing volley, in his 6-7 (6-8) 6-0 7-6 (7-3) victory over Jaume Munar.

World number 38 Diego Schwartzman won 6-1 6-2 over fellow Argentinian Federico Coria, while 47th-ranked Jiri Lehecka got past Arthur Rinderknech 7-6 (7-4) 7-5.

Australia's Jason Kubler toppled Lorenzo Sonego 6-4 7-6 (7-4) in almost two hours, while 42nd-ranked Bernabe Zapata Miralles was beaten 6-2 7-6 (8-6) by Ugo Humbert.

Finland's Emil Ruusovuori triumphed with Constant Lestienne retiring down 6-4 4-1 and world number 46 Alexander Bublik was a shock casualty, going down 6-4 6-4 to Wu Ting-Lin.