LONDON (AP) Venus Williams sighed at the reporter's question.
After getting to her first Wimbledon semifinal since 2009, and first at any Grand Slam tournament since a year later, she was asked what she learned in recent times, while dealing with an energy-sapping disease and a series of earlier-than-usual exits from majors.
''It's hard to say just one lesson,'' she began. ''It's easy to be afraid; you have to let fear go. Another lesson is you just have to believe in yourself. You just have to. There's no way around it. You've got to believe in yourself. No matter how things are stacked against you, you just have to, every time.''
Williams never lost that belief, the self-confidence that she still could compete at the highest level, the certainty that it made no sense to give up, to retire from the tour.
''The good part is, I always felt like I had the game. This is always a plus, when you know you have the game,'' said Williams, who owns seven Grand Slam titles, including five at the All England Club, but none since 2008. ''So you just have to keep working until things fall into place.''
At age 36, they have.
On Friday at Wimbledon, Williams will meet No. 4-seeded Angelique Kerber of Germany for a berth in the final. Kerber has won three of their previous five matchups.
The American is the oldest woman to participate in a major semifinal since Martina Navratilova did it at Wimbledon in 1994 at age 37.
''It's nice to see, because she puts in the work,'' said David Witt, Williams' coach. ''She hasn't been back, but not because of her play. Any given tournament, she's capable of beating anybody in the tournament. It's just a matter of winning six, seven matches in a row and keeping your level of play at a high level.''
Someone who knows all about that is Williams' younger sister, No. 1-seeded Serena, who faces 50th-ranked Elena Vesnina in Friday's other semifinal. If Vesnina - who has never so much as taken a set off Serena in five previous meetings - were to pull off the upset, she would be the first unseeded woman to reach the Wimbledon final in the Open era, which began in 1968.
The 29-year-old Russian had never been past the fourth round at a major before this week.
Serena, meanwhile, is bidding for her seventh Wimbledon championship and, of even more significance, her 22nd Grand Slam trophy overall, which would equal Steffi Graf for the most in the Open era (Margaret Court holds the all-time mark of 24).
Serena has come close to drawing even with Graf before: At the U.S. Open last September, she lost to Roberta Vinci in the semifinals while aiming for a calendar-year Grand Slam; at the Australian Open in January, she lost to Kerber in the final; at the French Open in June, she lost to Garbine Muguruza in the final.
Way back in 1999, the Williams sisters both reached the semifinals of the U.S. Open. Now here they are, almost 17 full years later, both in the semifinals of a Grand Slam tournament for the 11th time. On all 10 previous occasions, one or the other took home the trophy.
If both win Thursday, they would play each other on Saturday in what would be the siblings' ninth meeting in a Grand Slam final and fifth at Wimbledon.
For Serena, it would mean she's participated in the last three major title matches, seven of the past eight.
For Venus, it would be her first Grand Slam final since 2009, when she lost at Wimbledon to - guess who? - Serena.
''With everything she's been through, I think it's built a ton of character in her,'' Serena said, ''and in me, just by being around her.''
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