Switzerland's Roger Federer celebrates with the championship trophy during the awards ceremony after his victory against Spain's Rafael Nadal in the men's singles final on day 14 of the Australian Open tennis tournament in Melbourne on January 29, 2017. GREG WOOD/AFP/Getty Images

Many people thought Roger Federer's grand slam-winning days were behind him, but he defied his age and conventional logic to seal his 18th major title at the Australian Open.

The Swiss master, returning from the longest injury break of his career, capped a resurgent fortnight with a five-set victory over his long-time rival Rafael Nadal which extended his record haul of major singles titles.

His latest grand slam win was perhaps his most surprising, as Federer last won a big title at Wimbledon in 2012 and at 35, his best days were considered over.

But Federer beat Nadal 6-4 3-6 6-1 3-6, 6-3 to become the second oldest major-winner in the post-1968 Open era, after Ken Rosewall won the 1972 Australian Open aged 37.  It was Federer's fifth Australian title in his sixth final, and ended a long, seven-year wait to win again in Melbourne after his 2010 triumph over Andy Murray.