Brisbane, Jan 3 (IANS): Seventeen-time Grand Slam winner Roger Federer shot down concerns about his suspect fitness, saying he is charged up to win an elusive 18th Major at this month's Australian Open.

The 33-year-old has arrived here to play the season-opening tournament Brisbane International, starting Sunday, with no back spasms complaints that troubled him late in 2014.

He kept himself match-fit in the off-season coming down to India to play in the International Premier Tennis League (IPTL) and also turned up for exhibition matches.

"It can happen to anyone's back, those sort of spasms," Federer, the Brisbane International's top seed, was quoted as saying by news.com.au Saturday.

"You get over it quickly and thankfully before the Davis Cup final it started to get better. It was a long wait. I was lucky to make it."

Federer lead Switzerland to their maiden Davis Cup triumph against France last year but crippling back spasms forced him to withdraw from the Association of Tennis Professional's (ATP) Tour's year-end final against Djokovic in late November.

But the right-hander downplayed questions on his fitness.

"I went to India (for the International Premier Tennis League exhibitions) and had a charity match on Dec 21, so I've been keeping quite busy. I didn't have a big break," the world No.2 said.

"I will have a break after the Australian Open. It feels like it's ongoing and I have never really struggled at the Australian Open. I'm feeling good now and have had no hiccups in all the practice I have done. I'm very positive, the past few weeks."