The 33-year-old American, who won the last of her seven Grand Slam singles titles in 2008, recovered from a poor second set tie-break with a series of electrifying shots and acrobatic volleys in the decider, completing victory with another ferocious forehand cross-court after a shade over three hours.
“It’s hard to believe it’s my first semi-final in Tokyo after all these years,” said Williams.
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