Stockholm - Gastao Elias of Portugal stunned top-seeded Gael Monfils 7-6(4), 6-1 in the second round of the Stockholm Open on Thursday.
Elias booked a slot in the quarter-finals against Jack Sock of the US, who edged Dustin Brown of Germany 7-6 (5), 4-6, 6-4.
Ranked 61 in the world, Elias saved four break points against the seventh-ranked Monfils. He celebrated the win by jumping into the air like Portuguese soccer star Cristiano Ronaldo.
No 2-seeded Grigor Dimitrov also advanced by beating Jurgen Zopp of Estonia 6-3, 6-2, and will face Kevin Anderson of South Africa in the quarter-finals.
Anderson saved two set points in the first set to defeat Ryan Harrison of the US 7-6 (8), 6-4.
Juan Martin del Potro set up a quarter-final against Ivo Karlovic by beating Nicolas Almagro of Spain 3-6, 7-6 (1), 6-3.ATP Stockholm tournament results on Thursday (x denotes seeding):
Gastao Elias (POR) bt Gael Monfils (FRA x1) 7-6 (7/4), 6-1
Jack Sock (USA x6) bt Dustin Brown (GER) 7-6 (7/5), 4-6, 6-4
Tobias Kamke (GER) bt Radu Albot (MDA) 7-6 (10/8), 6-3
Juan Martin Del Potro (ARG) bt Nicolas Almagro (ESP) 6-4, 6-3
Kevin Anderson (RSA) bt Ryan Harrison (USA) 7-6 (10/8), 6-4
Grigor Dimitrov (BUL x2) bt Jurgen Zopp (EST) 6-3, 6-2