Serena Williams has proved that age is just a number in 2015 as the 34-year-old won three out of the four Grand Slams to complete the 'Serena Slam'.
She was, however, denied a shot at the first calendar Grand Slam in 27 years as Roberta Vinci, a doubles specialist ranked 43 in the world and rated a 300-1 chance by bookmakers, caused seismic shock waves by upsetting the defending champion and world No 1 2-6 6-4 6-4 in semi-finals of the US Open.
Serena will be eyeing Steffi Graf's record of 22 majors in 2016 and might even get the opportunity to catch the great Margaret Court on 24 Grand Slam titles.
But she will hope to stay fit and healthy and with talented stars such as Garbine Muguruza, Belinda Bencic and Madison Keys flying up the world rankings.
Williams started the year in scintillating fashion by securing her 19th Grand Slam title and sixth in Australia after recording her 16th straight victory over Maria Sharapova in the final.
She moved ahead of Chris Evert and Martina Navratilova on the all-time major winners' list and in an emotional speech after collecting her trophy, she said: "Growing up, I wasn't the richest, but I had a rich family in spirit and support, and standing here with 19 championships is something I never thought would happen. I just went on court with a ball, a racquet and a hope, that's all I had."
At Roland Garros, Williams overcame a viral infection to stave off Lucie Safarova's upset bid to prevail 6-3 6-7 (2-7) 6-2 in the final.
"The lowest point was definitely last night [Friday]," Williams said. "If you score it out of 10, where 10 is being taken to hospital, I went from a six to a 12 in a matter of two hours. I was miserable. I was literally in my bed shaking. I didn't think I was going to be able to walk, let alone compete. But I just told myself to think positive."
At Wimbledon, Britain's Heather Watson gave her a major fright in the third round, but the American eventually won through and went on to claim sixth Wimbledon title, beating the highly-rated Spaniard Garbine Muguruza 6-4 6-4 in the final to hold all four major titles at the same time.
Author @jk_rowling summed up Serena's achievement by tweeting: "#SerenaSlam! I love her. What an athlete, what a role model, what a woman".
She went into Flushing Meadows with the chance to become only the fourth woman to complete a calendar-year Grand Slam.
Williams stood on the brink of history and joining Maureen Connolly, Margaret Court and Steffi Graf as the only women to win a pure Grand Slam.
But her dreams came crashing down at the penultimate hurdle, losing to 32-year-old Italian Vinci in one of the greatest shocks in sporting history.
Williams insisted she had not buckled under the weight of expectation from the Ashe Ashe Stadium crowd. "I never felt pressure," she said. "I never felt that pressure to win here. I made a couple of tight shots, but for me it's normal in any match to make two tight shots. Other than that, I don't think I was that tight.
"I felt very happy to get that win at Wimbledon. I did win three Grand Slams this year. I won four in a row. It's pretty good."
And that was the end of Serena's season ... but have no fear because she he will be back fitter and stronger than ever, no doubt, in 2016.
Vinci went on to lose to her compatriot Flavia Pennetta in the first ever all-Italian final while at the WTA Finals, Agnieszka Radwanska conquered Petra Kvitova in a true underdog story to win the biggest title of her career. And that was that … roll on 2016!