MELBOURNE, Jan 17 (Reuters) - Third seed Grigor Dimitrov suffered a huge scare against 186th-ranked qualifier Mackenzie McDonald before holding his nerve in a tension-charged deciding set to win 4-6 6-2 6-4 0-6 8-6 and reach the third round of the Australian Open on Wednesday.
Bulgarian Dimitrov, a semi-finalist at Melbourne Park last year, fell in a huge hole in the fourth set against the free-swinging American, whose shot-making and composure made a mockery of his humble ranking.
Dimitrov had to wait and hope for McDonald to falter under the lights at Rod Laver Arena, and finally the American did with a double-fault that gave up match point.
Dimitrov held on until McDonald slammed a forehand into the net putting his opponent into a third round clash with Russian 30th seed Andrey Rublev. (Editing by Christian Radnedge)