Serena Williams says she discovered just minutes before her match against Johanna Konta last month that the man convicted of killing her half-sister had been released on parole.
Briton Konta inflicted the worst defeat of Williams’ career by 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 aged 31.
“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 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 practise what I preach, and teach [daughter] Olympia that as well. I want to forgive. I have to get there. I’ll be there.”