Wild card Thiago Monteiro made his ATP World Tour debut in front of his home crowd in Rio de Janeiro on Wednesday, and what a debut it was. The 21 year old, No. 338 in the Emirates ATP Rankings, knocked off third seed Jo-Wilfried Tsonga 6-3, 3-6, 6-4 in just over two hours on Quadra Guga Kuerten to advance to the second round.
The Rio de Janeiro resident, who reached an ATP Challenger Tour semi-final in the city last month, landed 67 per cent of first serves and scored the only break of serve in the deciding set to eliminate Tsonga, who was coming off a quarter-final appearance in Buenos Aires last week.
He became the first player to win his debut against a Top 10 player since Guido Pella (d. Tipsarevic 2013 Dusseldorf) and the first player ranked 300 or lower to beat a Top 10 player since Albano Olivetti (d. Fish 2012 Marseille).
Dominic Thiem, who is coming off a title in Buenos Aires, held on for a 7-5, 7-5 win over Diego Schwartzman to advance to the quarter-finals. The fifth seed led 3-0 in the second set before his opponent swept the next four games, but the World No. 19 broke serve two more times to close out the win.
No. 7 seed Fabio Fognini was not so fortunate. The Italian was forced to retire with an abdominal strain while leading 6-4, 1-3 against Spanish qualifier Daniel Gimeno-Traver.

Wawrinka survives Stakhovsky in Marseille
Stan Wawrinka saved two match points in a 6-4, 4-6, 7-6(8) second-round win over Sergiy Stakhovskyin Marseille on Wednesday.
Last year, the Ukrainian got the better of Wawrinka in the quarter-finals of the Open 13 Provence, but this time, the Swiss hit two unplayable serves in the deciding tie-break to stave off elimination, then landed a backhand pass on his second match point to seal the win in two hours.
“It was a great battle, I was lucky to get out of this,” said Wawrinka, who was down a break in the deciding set. “The third set was complicated. I was lucky to be able to break him at the end of the match.”
The top-seeded Swiss, playing in his first match since the Australian Open (l. to Raonic), improved to 8-1 on the season and is gunning for his second title of the year (Chennai).
Stakhovsky came to net 62 times in the pair’s third FedEx ATP Head2Head meeting (Wawrinka now leads 2-1) but was on the receiving end of 49 Wawrinka winners, the last one on the final point of the match.
Wawrinka’s quarter-final opponent will be good friend and eighth seed Benoit Paire, or French qualifierVincent Millot, who beat Rotterdam semi-finalist Nicolas Mahut 6-7(1), 6-2, 6-3.
Rising star Quentin Halys fought his way into the second round with a 6-7(5), 6-2, 6-3 win over qualifierDavid Guez. The 19-year-old wild card claimed his first tour-level win at the Australian Open (d. Dodig) and is currently No. 171 in the Emirates ATP Rankings. He will face Andrey Kuznetsov for a place in the final eight.
No. 4 seed Marin Cilic rallied to defeat Robin Haase 4-6, 6-3, 7-5 in just over two hours. In the second-round encounter, Cilic struck 12 aces and converted four of 16 break points to improve his record against the Dutchman to 5-0.
No. 6 seed David Goffin advanced to the quarter-finals when Mischa Zverev retired with the Belgian leading 6-1, 2-0.