A wasteful Rafael Nadal fought past Federico Delbonis in the Australian Open second round on Thursday.

Nadal wasted numerous break points on Rod Laver Arena, needing two hours, 30 minutes to overcome Delbonis 6-3 7-6 (7-4) 6-1.

The world number one was below his best, but was still good for Delbonis, who had won just 10 games in his previous three meetings with Nadal.

The Spanish star remained on track in his bid to join Roger Federer on a men's record 20 grand slam titles, though, with countryman Pablo Carreno Busta awaiting him in the third round.

Nadal squandered six break points in a marathon 22-point second game, but would take his next chance when Delbonis sent a tame backhand into the net.

That solitary break would be enough for Nadal to win the opening set, crushing a forehand winner to take it in 49 minutes.

Delbonis dug himself out of a 0-40 hole to hold in the first game of the second set and saved two more break points in the fifth game.

Another three chances came and went for Nadal in the seventh game before an ace from Delbonis – who looked to be working his way into the contest – denied the Spaniard again in the 11th game.

A wonderful lob helped Nadal set up a 3-1 lead in the tie-break, an advantage he would not relinquish on his way to a two-sets-to-love lead.

Delbonis' resistance was finally broken and so was his serve in the fourth game of the third set as Nadal – who kissed a ball girl after a wayward forehand – booked his spot in the third round.

STATISTICAL BREAKDOWN 
Rafael Nadal [1] bt Federico Delbonis 6-3 7-6 (7-4) 6-1

WINNERS/UNFORCED ERRORS 
Nadal – 33/29
Delbonis – 22/43

ACES/DOUBLE FAULTS 
Nadal – 8/1
Delbonis – 2/8

BREAK POINTS WON 
Nadal – 3/20
Delbonis – 0/0

FIRST SERVE PERCENTAGE 
Nadal – 69
Delbonis – 63 

PERCENTAGE OF POINTS WON ON FIRST/SECOND SERVE 
Nadal – 85/61
Delbonis – 65/44

TOTAL POINTS 
Nadal – 116
Delbonis – 83