New Zealander Michael Venus and his South African partner Raven Klaasen are through to the quarter-finals of the Miami Open after downing American's John Isner and Donald Young.
They won 7-5, 6-3 in just over an hour against two players who have achieved considerable doubles success despite their reputation as singles specialists.
Games went with serve until the 11th game of the opening set when Venus and Klaasen broke Young with their third break point of the set. Venus then served out the first set 7-5. In the second set, at 3-3, they broke Young for a second time and then Isner for the win.
They will meet fourth seeded Bryan twins Bob and Mike, who beat Kiwi Marcus Daniell and his British partner Dominic Inglot in the first round.
The Bryan's are the most successful team in world doubles with 16 Grand Slams and over 100 ATP Tour titles together.
