Serena Williams ended a 14-year boycott of Indian Wells with a 7-5 7-5 win over Monica Niculescu on her return to the California tournament.
Williams was booed and heckled during her last appearance at the event in 2001, when she won the final.
This time she was given a standing ovation as she walked on to court, before sealing victory in two hours.
"It is one of the biggest moments of my career," said the 33-year-old. "I feel like I've already won this tournament."
The American was watched by several family members, including her mother, as she returned to the scene of her 2001 defeat of Belgian Kim Clijsters.
That final was marred by the behaviour of some fans who heckled her and her family, apparently in response to sister Venus withdrawing injured from the semi-final between the siblings.
|Serena Williams at Indian wells|
|Williams had played 651 matches and won 55 WTA titles since she last competed at Indian Wells in 2001. On her three previous appearances in the main draw, from 1999 to 2001, she had a 14-1 record that included titles in 1999 and 2001 and a quarter-final in 2000.|
Her father, Richard, later accused fans of racial abuse and the Williams sisters had not returned to the event until Serena's match on Friday, with Venus still staying away.
"I felt like I made the right decision and I knew I wanted to do it," said Serena.
The world number one, top seed for the event, initially looked nervous against her Romanian opponent and made 48 unforced errors before eventually winning a lengthy and hard-fought match.
"I didn't know what to expect," Williams said of the standing ovation.
"In the last couple of moments leading up to it, I was focused on warming up for the match and I wasn't really prepared for that. I was overwhelmed by it.
"It was such a warm feeling. It made me feel incredibly well. And receiving the love from the crowd here, it really meant a lot to me."