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Five-time champion Venus Williams reached the Wimbledon semi-finals for the first time since 2009 with victory over Kazakhstan's Yaroslava Shvedova.
Eighth seed Williams - at 36 the oldest Grand Slam semi-finalist for 22 years - beat unseeded Shvedova 7-6 (7-5) 6-3.
An all-Williams final remains possible after top seed Serena beat Russian Anastasia Pavlyuchenkova 6-4 6-4.
In Thursday's semis, Serena will play Russia's Elena Vesnina and Venus will take on Germany's Angelique Kerber.