With all of the top seven seeds making the last eight, the latter stages of the competition were always going to be tough, and so it proved for Heliovaara and Patten, who dropped a set and were taken to tiebreaks for the first time in the tournament.
Both pairs were in control of their service games early in the first set, though Andreozzi and Guinard were forced to save break point in the 10th game. That missed chance proved costly for the Finn and Brit, who had the tiebreak at their mercy at 6-4 up, only to throw it away and lose 9-7, handing the seventh seeds a 7-6 set win.
The first nine games of the second set were a carbon copy of the first, with not a single break point chance. But again, game 10 was the most dramatic, as the reigning Wimbledon champions almost crashed out, but managed to save three match points and level things up at 5-5.
Another tiebreak was needed, but this time Heliovaara and Patten turned on the style, forcing four successive losses of serve from the Argentinian and Frenchman to win 7-3, confirming a 7-6 win of their own.
Having survived the scare, the world number ones finished strongly in set three - having gone 3-2 up, they didn't drop a single point on their opponents' next two service games, and held their own, to win the set 6-2 in 30 minutes - a heartbeat compared to the 2:20 match time - and take the 6-7, 7-6, 6-2 win.
In the semi-finals, Heliovaara and Patten will face the fifth seeds - the USA's own Christian Harrison and Patten's compatriot, Neal Skupski.
