Alexandr Dolgopolov has stunned Stanislas Wawrinka to progress to the quarter-finals at the Miami Masters, beating the Australian Open champion 6-4 3-6 6-1.
The Ukrainian needed just a single break to clinch the opener, but the world number three rallied in the second, winning three games in a row to level the match.
Dolgopolov had two chances to break the Swiss in the second, but was unable to capitalise on his opportunities, ensuring that the match went to a deciding set.
However, the 22nd seed raised his game again, securing two early breaks as Wawrinka held serve just once, allowing Dolgopolov to wrap up his second win against a top 10 ranked player this month following his win over Rafael Nadal at Indian Wells.
Dolgopolov faces either Tomas Berdych or John Isner in the last eight.