THE bags under his eyes were growing and his head may have felt a little heavy but Stan Wawrinka could not keep the smile off his face yesterday as he tried to put into context what he had achieved by winning his first grand slam title.
The Swiss - now the top-ranked player from his country and the world No. 3 to boot - barely had time for sleep yesterday before he completed another round of media commitments.
He did not even have time to chat for long with Roger Federer, his friend, inspiration and the man he has overtaken in the rankings, who called to offer his congratulations soon after the final. "He texted me and he called me," the 28-year-old Wawrinka said. "He was quite crazy for me; really, really happy. He's been in that situation so many times. He knows the feeling.
"As I always say, he is my first supporter. He is always there. If he can help me he is always there. I talked last night with him. I just said that when I had time I would call him back."
Having beaten Rafael Nadal to win the Australian Open about 14 hours earlier, Wawrinka was just about coming to terms with things. Just about. "It still feels like a dream because it's a grand slam title," he said, giving the trophy a tap just to make sure it was real. "It's something just amazing for me. It's good to wake up with that trophy."
Though Nadal was injured in the final, that should not take away from the enormity of Wawrinka's efforts. It is the first time anyone other than Nadal, Novak Djokovic, Roger Federer or Andy Murray has won a grand slam since Juan Martin Del Potro broke through at the US Open in 2009.
The manner of the Swiss' play throughout the fortnight was nothing short of exceptional but winning the title was something few people believed possible. "I don't think a lot of people in Switzerland were expecting me to win a grand slam," he said. "Last year I wasn't close at all, making the quarter-final in a grand slam was my best result."
His decision last April to join up with coach Magnus Norman, a former world No.2 and a runner-up at the French Open, has changed everything. Norman may have a calm, reassuring manner but the Swede, who also coached Robin Soderling to two grand slam finals, has instilled a belief in Wawrinka.
"I realised last year that I was close to making a big result," said Wawrinka. "I made one semi-final [at the US Open]. But last year I lost a semi-final in five sets to Novak and, even if I had won that match, I would have had to play Rafa in the final. For me that was too much. That's why I always say I had never dreamed about winning a grand slam. It was just not my level, not my goal.
"But again I think I have a good mentality to always try to improve. I always go on court trying to win and to enjoy it. I showed this since the beginning of this year, that I am playing my best tennis. And when I play my best tennis I can beat all the players."
Norman tried to downplay his role in the victory, praising Wawrinka's former coaches - including Peter Lundgren and Severin Luthi, Federer's coach and the Swiss Davis Cup captain - who was also there throughout the fortnight. "Maybe I helped him with the last step, small things, but all credit to Stan," Norman said.
What comes through in speaking to Norman, to Federer and to all the players, including Nadal, though, is that Wawrinka is quite simply, a good guy.
"I took the job because Stan is a really humble guy, a nice guy," Norman said. "I didn't take the job because I thought he was going to be top five or something like that but I knew he had great results in him. It is great to work with a guy who likes to work hard, but this is a little bit beyond my expectations."
Wawrinka has spent most of his life in Federer's shadow. However, with the great man today slipping down the rankings to eighth - two places behind Murray, who dropped points after reaching the final last year - it is time for a new Swiss hero.
"We'll see in the next grand slam but for sure, it's a different level now," he said. "I realise that when I play my best tennis I can beat Novak, I can beat Rafa, in a grand slam, in a final, in a semi-final.
"Everybody will expect me to make some great results in the next tournament, the next grand slam. But I will keep doing my things, keep trying to work with my team how to improve and go back to practice."
Wawrinka said that he will always think of himself as second to 17-time grand slam title winner Federer, no matter what the rankings say. When he returns to Melbourne Park next year and makes his first walk through the corridors, though, he will see a photo of himself alongside the likes of Federer, Nadal, Djokovic and other great champions at the Australian Open.
"The first thing I will do, I'm going to come back and take a picture of myself, that's for sure," he said. "It's big when I see those champions. They are the real champions and to be there is just something crazy."
Wawrinka has a Davis Cup commitment to fulfil this weekend in Serbia but once that is done, he will finally take some time to relax and reflect a little deeper. At some stage, he will realise he is a grand slam champion. No-one deserves it more.