Romanian qualifier Marius Copil has upset third-seeded Frenchman Gilles Simon in the Brisbane International second round.

World No.147 Copil – ranked 128 places lower than his rival – proved too strong for the former Australian Open quarter-finalist, prevailing 7-5 6-3 in their first-ever clash.

Former world No.6 Simon had no answers as Copil booked a quarter-final against the winner of Lleyton Hewitt’s second-round meeting with sixth-seeded Spaniard Feliciano Lopez.

Earlier, eighth-seeded Frenchman Jeremy Chardy beat compatriot Nicolas Mahut 7-5 6-7 (7-4) 6-3 to move into the quarter-finals.

World No.34 Chardy, 26, will play the winner of Australian Sam Groth’s second-round clash with South African fourth seed Kevin Anderson to be played on Thursday night.

Mahut had made more of a name for himself in Brisbane as Roger Federer’s doubles partner at the tournament but kept former Wimbledon junior champion Chardy honest by clinching the second set.

But world No.50 Mahut, 31, could not sustain the pressure and buckled as Chardy emerged triumphant.