Serena Williams said Monday that she "can't wait for the future" as she warmed up for her return to the WTA Tour at the Tie Break Tens exhibition at Madison Square Garden. The 23-time Grand Slam champion is competing at the elite Indian Wells hardcourt tournament this week, her first tour action since her 2017 Australian Open triumph.

Williams was pregnant when she lifted the trophy in Melbourne last year, and missed the rest of 2017 awaiting the birth of her daughter in September.

Monday's event, which featured eight players facing off in 10-point "super tie breaks" as they vied for a $250,000 winner's prize, was a chance to sharpen her skills.

Williams bowed out in the second round, gaining a 9-7 lead over China's Zhang Shuai but eventually falling 13-11.

"It was good," she said of the experience. "I wish I would have made a few more shots."

Williams opened the laid-back event with a 10-5 victory over Marion Bartoli, the 2013 Wimbledon champion who announced in December she was planning to return to the court more than four years after retiring in the wake of her only Grand Slam triumph.

After correcting the protocol for the "rock-paper-scissors" game used to determine who served first, Williams fell behind 4-2, but a double-fault from Bartoli followed by two aces from Serena saw the American great ahead 5-4.

A couple of forehand winners and a service winner saw Williams take an 8-4 lead, and she finally finished it off with another winning serve.

"It feels different, it feels good," said Williams, who returned to competition with a Fed Cup doubles loss alongside her sister Venus last month.

The birth of Williams's daughter, Alexis Olympia, was followed by complications that scuppered the player's plans to defend her title in Melbourne.

But Williams says she's aiming to be back at her best -- apparently more than comfortable with coach Patrick Mouratoglou's comments to wtatennis.Com that her goal for this season "will be to win Grand Slams."

"I think everyone should have high expectations," said Williams, who will be unseeded at Indian Wells and open her campaign against 53rd-ranked Zarina Diyas of Kazakhstan.

"That's the message that I'm sending."

Bartoli, who was forced to pull out of an exhibition event at Wimbledon last year because of a mystery virus and dramatic weight loss, has said she was targeting a return to the WTA Tour at the Miami Open later this month.

However, the 33-year-old told AFP her timetable would depend on how her body holds up to training.

"I do not know if my shoulder and my knees are going to hold, there are so many question marks," she said.

"What is certain is that I will not return to the court until I consider myself 100 percent. I stopped the competition for five years -- and I'll be back when I'm 100 percent."