MELBOURNE (Reuters) - France's Jeremy Chardy sprung a major upset at the Australian Open on Saturday by dumping sixth seed Juan Martin del Potro out in the third round with a 6-3 6-3 6-7 3-6 6-3 victory.

The 36th-ranked Frenchman charged out of the blocks to take a two-set lead by dominating at the net, but the former U.S. Open champion served strongly to level.

Chardy captured the decisive break when leading 4-3 in the fifth set and calmly served out the three hour and 45 minute match, sealing it with an ace.

Chardy will next play Andreas Seppi.

(Reporting by Ian Ransom; Editing by Patrick Johnston)