Rafael Nadal maintained a positive attitude following an opening-round defeat to No. 127-ranked Michael Berrer in Doha.

It was the Spaniard's first ATP match since returning from an injury- and illness-plagued season, and only his third ATP tournament since Wimbledon. A slow start is normal, suggested Nadal, saying, "You can see all the comebacks from a lot of players when they were injured from long time, the comebacks are tough. I'm not an exception.

"I am another one, that will be tough for me. I'm going to work hard to try to make it less tough as possible, but my motivation and my hunger to keep doing the things well still the same, so I am sure that I gonna come back to my best."

Though he twice returned from a knee injury to dominate in 2010 and 2013, the 28-year-old is not anticipating a repeat. "And 2013 was amazing comeback, but as I say the other day, I come back on perfect conditions for me, on clay, [ATP] 250 tournaments. All the facts was on my favor," he said. "This time is a little bit different. This one is the third one, so we will see. We will see how the thing goes in a couple of months. I wanted to start well. Was not the case today. I want to play well in the Australian Open."

Nadal acknowledged that his form is questionable going into the Australian Open, but for the nine-time French Open champion, who won Down Under in 2009, there is time to turn things around.

"It is true if I'm able to practice well and find my rhythm, if I'm able to win a couple matches there, then anything can happen," he said. "I gonna think that I have my chances."

Despite his recent lack of match practice, Nadal said he was not inclined to take a wildcard into Auckland or Sydney, but will stay and play doubles in Doha.