Melbourne, Jan 19 (IANS): World No. 2 Rafael Nadal is expected to be out of action for six to eight weeks after sustaining a grade 2 injury during his second loss at the Australian Open.

In Wednesday's match at 3-4 in the second set against Mackenzie McDonald, the Spaniard chased a forehand wide and aggravated the injury that he admitted he had felt for a couple of days.

"Good afternoon. I have carried out medical tests after the defeat yesterday. The MRI shows a grade 2 lesion in the Iliacus Psoas of the left leg. Now it's sports rest and anti-inflammatory physiotherapy. Normal recovery time 6 to 8 weeks," Nadal tweeted.

The iliopsoas muscle is located in the hip. Nadal was trailing 4-6, 3-5 when he took a medical time-out after moving to his left to chase a forehand and pulled up in pain with an apparent upper left leg injury.

The 36-year-old Spaniard returned to play out the match but he was clearly not 100 per cent physically fit for the rest of the match and the McDonald wrapped up the win 6-4, 6-4, 7-5 in two hours and 32 minutes.

The six to eight weeks timeframe means Nadal could be fit to play by the start of the clay court season that includes a French Open, where Nadal is seeking his record 15th title.