The Serbian has qualified for the eight-woman tournament for the first time in three years after a season that has seen her return to the top 10.
From 2007 to 2010, Jankovic was a fixture in the top 10 and, after reaching the final of the US Open in 2008, she finished the season as world number one.
But injuries took their toll, her confidence wilted and last season she briefly fell out of the top 30.
Jankovic said: "It's been a great journey making it to the championships. I have worked very hard since the beginning of the year.
"I got injured in Australia, tore my muscle, and couldn't train for three weeks. After that, I called my brother and I started working with him, and he told me from the beginning that his goal is to bring me back to the top.
"So with the hard work, we believed. I got new motivation and it gives me great satisfaction that I was able to make it here and that all that hard work has paid off.
"I want to try to improve even more. I believe there is a lot of room for improvement in my game, and I think mentally, as well. I feel so much more confident.
"I want to get back to top five. That's my next goal. So we will see. That's for next year, of course."
Consistency has been the bedrock of Jankovic's success this year, with the 28-year-old reaching at least the quarter-finals of eight tournaments, including at the French Open.
Explaining the transformation, she said: "There is a reason why you were losing.
"So you have to figure out a way to win again and try to do the right things. And over the years I think I have learned a lot. I have made a lot of mistakes and I have learned what works for me.
"Now as a 28-year-old I can use that to my advantage. I have a lot more knowledge, a lot more experience. I think I can do and show a lot more in my tennis career.
"So I'm ready to work hard and to show the world some great tennis performances.
"I love the competition, I love the satisfaction of winning, I love playing against the best tennis players in the world. I enjoy spending time on the court, and as well I enjoy spending time on the practice court, which was at times not the case."
World number eight Jankovic, who is the only different face from 12 months ago, sits out Tuesday's play and will meet Li Na on Wednesday.
Second seed Victoria Azarenka opens proceedings against Sara Errani before defending champion Serena Williams meets Angelique Kerber and Agnieszka Radwanska plays Petra Kvitova in the final match of the evening.