Serena Williams says she discovered that the man convicted of killing her half-sister had been released on parole just minutes before her match with Johanna Konta last month.
Briton Konta inflicted the worst defeat of Williams’ career, winning 6-1 6-0 in the first round of the Silicon Valley Classic in San Jose.
Williams’ elder half-sister Yetunde Price was shot dead in 2003.
“I couldn’t shake it out of my mind,” said the 23-time Grand Slam champion.
Robert Maxfield was jailed for 15 years in April 2006 and Williams, 36, attended the sentencing.
She told Time magazine: “No matter what, my sister is not coming back for good behaviour.”
Price was 31 when she was shot dead in Compton, Los Angeles. Her children were 11, nine and five at the time.
“It’s unfair that she’ll never have an opportunity to hug me,” Williams said.
“It was hard because all I think about is her kids – what they meant to me and how much I love them.
“I would like to practice what I preach, and teach [Williams’ daughter] Olympia that as well. I want to forgive. I have to get there. I’ll be there.”
‘That’s not being Serena’
The US Open gets under way in less than two weeks with Williams vying for a seventh singles title at Flushing Meadows.
Williams, who returned to the women’s tour earlier this year after giving birth to Olympia last September, admitted she is at the “start of a long comeback” after losing in the second round of the Cincinnati Open to Czech Petra Kvitova on Tuesday.
She returns to New York having lost in the US Open semi-finals in both 2015 and 2016.
“I’m trying to get a new vibe there,” said the current world number 27.
“But I’m not going in there thinking I’m going to lose. That’s not being Serena. That’s being someone else.”