Chilean Fernando Gonzalez produced an inspired performance to upset fifth seed James Blake 7-5, 6-4, 7-6 and reach the Australian Open quarter-finals on Monday.
The 10th seed, who knocked out home favourite Lleyton Hewitt in the last round, continued his hot streak to overwhelm the in-form Blake, who had not lost a set on his way to the last 16.
The players exchanged breaks in the first set and Gonzalez saved three set points before serving out to love to steal it.
Blake, 27, made a number of unforced errors and Gonzalez took full advantage to surge into a 2-0 lead.
The 26-year-old south American broke again early in the third set and served for the match at 5-4 but he froze on the brink of victory, allowing Blake to break back and force a tiebreak.
Gonzalez refused to be denied, however, dominating the tiebreak before winning it 7-3 with an ace to clinch victory in two hours six minutes and reach the quarter-finals at Melbourne Park for the first time in seven attempts.
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