ONLY those closest to tennis ace Lleyton Hewitt know if this Australian Open will be his last.
When he takes to the court at Melbourne Park, possibly Rod Laver Arena, Hewitt will mark an 18th consecutive Australian Open appearance.
It's a remarkable feat, whether he is your favourite player or not.
To have played and succeeded on the professional tennis circuit for so long is testament to his skill, mental toughness and support of his inner-sanctum.
Hewitt's victory against Swiss star Roger Federer at the Brisbane International shows the Australian star is far from done, just yet.
Injuries have plagued Hewitt for many seasons, but when he's fit and healthy there's a warrior ready to take on any player.
First-round opponent at this Australian Open, Italian 24th seed Andreas Seppi will be well aware of Hewitt's form and fighting quality.
Seppi not only has to face Hewitt's forehand and backhand drives and volleys, but a vocal home crowd.
Let's Go Lleyton has echoed around tennis courts thousands of times.
Let's Go Lleyton has echoed around tennis courts thousands of times
Hewitt's career record is almost 600 wins across 836 matches at Grand Slam, ATP Tour and Davis Cup level.
The most memorable were victory in the 2001 US Open against Pete Sampras, and the 2002 Wimbledon final against David Nalbandian.
Both triumphs were achieved in straight-sets and the height of Hewitt's dominance.
He also reached the 2004 US Open final and 2005 Australian Open final.
When it comes to representing their country, Hewitt's play in Davis Cup puts him among Australia's best in all sorts of sports.
Throughout his career the gun from South Australia has polarised tennis fans.
His record in five-set marathons, Davis Cup clashes and to be on tour for almost two decades are the stuff of legend.
Not so great are the on-court controversies.
Tennis is highly-strung and many of the best, whether it be John McEnroe, Jimmy Connors, Ilie Nastase, or Lleyton Hewitt, have let emotions override the thought process.
Gamesmanship or not, some of Hewitt's comments about umpires or linespeople made my blood boil.
As the summers have rolled on, Hewitt has mellowed in his behaviour and as such his popularity, shown by those cheering courtside or watching on TV, has risen accordingly.
Many watching this year's Australian Open will be hoping to hear C'mon shouted many more times.
How you will be remembered is for others to do.
Your actions go a long way to determining just how that is done.
In many ways Lleyton Hewitt has done a lot right and deserves to hold his place alongside Australian greats when he decides to call game, set and match on his playing days.