WAS there another sportsman on the planet able to derive as much personal validation from their efforts during 2011 as Novak Djokovic?

The 12-month period saw the 24-year-old Serbian achieve a pre-eminence in men's tennis which was startling for those who witnessed his faltering efforts to usurp the duopoly of Rafael Nadal and Roger Federer just a year earlier. He won 10 ATP tournaments, capturing three of the four Grand Slam titles, with only a late season shoulder injury depriving him of a place in posterity as his loss record crept up to six matches from 76 played. Melbourne Park was where it all began and Djokovic returns $12 million richer than last year. He also has acquired a large target between his shoulder blades.

That is because the rest of the field will be relentless in examining his body language and demeanour for signs of weakness. The merest hint of mental fatigue after the gruelling heroism of 2011 will provide huge encouragement. Conversely, an early season signal that normal service has been resumed after an injury-hit ATP Tour finals will be demoralising for the remainder of men's tennis.

"People will be looking for chinks in the armour straight away," said Darren Cahill, Andy Murray's former coach and ESPN pundit. "If he comes out, beats down the other players, wins the Australian Open and we see him in the same form as we saw for the best part of last year, that's going to be a real problem for the field. People are going to be expecting there might be a let down. People are going to be looking for him being a little bit tired or at least a little bit mentally tired. But if he doesn't show that and he comes out and plays at the same level, that's a real problem for just about every player."

The bad news for everyone else is that Cahill doesn't expect to see any New Year sluggishness from the Serb, who is a potential semi-final opponent of Murray's. "Any suggestion that he might have a little bit of a hangover for 2012, I'm not buying into it," he said. "He's going to have great feelings coming to Melbourne Park, because this is pretty much where it all started for him last year. Whether or not he can repeat it is a tough ask. But I don't think you'll see a drop in level from Novak's game."

If Djokovic was at breaking point in the final two months of last season, others are already dealing with complaints as 2012 begins. Rafael Nadal appears vulnerable, having admitted he has scheduled in some inactivity for next month as he rests a shoulder problem, while Roger Federer pulled out of the semi-finals at the recent Qatar Open with a nagging back complaint. As awkward as that may be, the Swiss player's victory in the ATP Tour finals shows a 17th Grand Slam title should not be discounted.

"It was incredibly important for Roger to finish last year well," Cahill said. "After the disappointment of the US Open and being so close to making it through to another final, it was really important for him to go off, clear his head, get back on court and feel like he can still match up with these guys. He's not getting any younger, but it's far too early to be drawing a red line through Roger Federer's name."

Part of the magic of the Australian Open resides in its capacity to spring a surprise, the chance of a highly-rated youngster or forgotten outsider to catch a poorly-prepared big name cold in the heat of an Australian summer. Ryan Harrison, Murray's first-round opponent, Canadian youngster Milos Raonic and home favourite Bernard Tomic may come into this category, while Juan Martin del Potro has a year of tennis under his belt after injury and could well step up again in the Grand Slams.

But any analysis of the probable movers and shakers in Melbourne must also touch on Murray. The Scot is third favourite with bookmakers, and Cahill feels he may have the Serb in his sights. Murray lost in straight sets to Djokovic in last year's final, but did inflict one of the Serb's six defeats, in the Cincinnati Masters final. "He's never far away when he plays Novak, he doesn't mind the match up," said Cahill. "He always believes he can win that match. And if he believes he can beat the top player in the world, I certainly believe he's not far away from winning a major."