Peter Luczak has moved into the quarter-finals of the Movistar Open in Chile following a straight-sets win over Spaniard David Marrero.
The 30-year-old Australian proved too good for the qualifier 6-3 7-6 (7-4) without facing a break point at any stage in their first career meeting at the top level.
Luczak will meet Juan Monaco in the final eight after he won an all-Argentine clash against Juan Ignacio Chela 6-3 7-5 in an hour and 29 minutes.
Monaco, the second seed, converted five of his seven break points to set up the win.
Third seed Thomaz Bellucci came through a near three-hour battle with local hope Paul Capdeville to reach the quarter-finals.
World No.143 Capdeville - born in the host town of Santiago but now resident in Miami - took the first set 7-5 but Brazilian Bellucci battled back to level.
He then held serve at 4-5 to stay in the final set and claimed the crucial break before serving out a 5-7 6-4 7-5 win.
He will next face Eduardo Schwank, who benefited from the withdrawal through injury of sixth-seeded fellow Argentine Jose Acasuso at one set all in their second-round clash.
Acasuso took the first set after winning a tie-breaker 7-3 but Schwank won the second 6-2 as an injury to Acasuso's left knee took its toll, ultimately forcing him out of the match before the deciding set could begin.
Meanwhile, top seeds Gael Monfils and David Ferrer avoided trouble on day four of the SA Tennis Open as straight-sets victories put them through to the quarter-finals in Johannesburg.
World No.13 Monfils, who is the No.1 seed for the Montecasino event this week, beat Josselin Ouanna 6-4 7-5 despite a determined display from his fellow Frenchman.
The two-time ATP tournament winner showed his class to seal victory on his first match point.
He will next play Yen-Hsun Lu after the Chinese Taipei star battled past wildcard entry Raven Klaasen 6-4 7-5. The No.7 seed needed close to two hours for the win against the plucky South African, who was given good support by those in the sparse home crowd.
Second seed Ferrer had little trouble, seeing off qualifier Filip Prpic 6-3 6-4.
The Spaniard, bidding for his eighth career title, won most points on first serve - 31 out of 42 - while he made the most of the Swede's failure to capitalise more on his six break points to ease to victory.
India's Somdev Devvarman also made sure of his place in the last eight after a comfortable 6-4 6-1 win over Brazilian Thiago Alves.
The 24-year-old was ruthless on his own serve, winning more than 80 per cent of his points in the first set.
The second set was even more comfortable for the world No.162, who will face Ferrer for a place in the semi-final.
And at the Zagreb Indoors, defending champion Marin Cilic eased into the quarter-finals at the expense of Austria's Daniel Koellerer.
The top-seeded Croatian, who reached the Australian Open semi-finals last week, ran out a 6-2 6-1 winner to set up a meeting with compatriot Ivo Karlovic.
Karlovic, the seventh seed, had a trickier time on court against French qualifier Alexandre Sidorenko before claiming a 7-6 (7-4) 7-6 (10-8) result in their second-round match.
Second seed Ivan Ljubicic saw his Zagreb challenge ended by Lukas Lacko, the Slovakian grinding out a 7-6 (7-3) 5-7 7-6 (7-5) win.
No.6 seed Benjamin Becker also bowed out of the tournament, throwing away a one-set lead to succumb 1-6 7-6 (7-4) 7-6 (8-6) to German countryman Philipp Petzschner.
Michael Berrer of Germany advanced to the last eight with a straightforward 6-4 6-3 victory over local wildcard Petar Jelenic.