Williams' sister Venus also participated, losing her only tie against Svitolina, and is hopeful about her sibling's impending Tour return.
The elder Williams sister has not played an official singles match in 15 months since winning last year's Australian Open, but her coach Patrick Mouratoglou has said the 23-time grand slam victor expects to be in tip-top condition for the year's second slam come May.
The 36-year-old brushed aside second seed Grigor Dimitrov to win his third title at the Rotterdam Open last month, having already been confirmed as the oldest world number one in history as a result of reaching the quarter-finals in the Netherlands. [But] I think we can say without doubt that this is her biggest challenge.
Mouratoglou said fans had to give Williams time to adjust to the rigours of the sport.
"This is a good sign for me, now I'm ready for the future". The 23-time Grand Slam champion won both of their previous matches, including a 6-2, 6-0 win in Indian Wells in 2015.
No one in the men's game can better Federer's haul of 20, the 36-year-old having won three of the past five slams as part of a stunning renaissance. Her opponent, on the other hand, didn't even make her main-draw debut at the tournament until past year. She hasn't played a match for more than a year, she has had a baby with a lot of complications post-delivery.
"Once I was asked by my coach, Pat (Cash), if I was going to be available around that time, I said, 'Yeah, I'll make myself available.' So it didn't take much thinking".
Williams, who is unranked as she has spent more than 12 months away from the tour, has been drawn to play Zarina Diyas of Kazakhstan in the first round in Indian Wells.
Azarenka hasn't been able to compete since Wimbledon because of the custody dispute over her son, but, as the 2012 and 2016 Indian Wells champion, she can't be counted out. The competitions she will play until then will help her and every day she progresses on her fitness.
"She took the decision to come back to tennis". I've always been an extremely motivated person.
"My expectations, I don't know what they are", said Williams. Though she has a 5-0 career record against Watson, an accomplished player in her own right, the extended time off the tour may make this a hard match for Azarenka.