Serena Williams overcame older sister Venus in straight sets to march on to the Wimbledon quarterfinals. Venus had triumphed in the most recent meeting between the most famous siblings in tennis, but the 35-year-old was unable to derail the world No. 1 on her path to a fourth consecutive Grand Slam title, losing 6-4 6-3 in one hour and eight minutes.

The younger of the two by 15 months, Serena led the head-to-head series 14-11 going into what could well be the last ever meeting between the pair on such a big stage. And she made a perfect start, breaking in the opening game to love and then holding serve still without losing a point. While she had needed a dramatic final-set fight back to beat Britain’s Heather Watson in Round 3, Serena began with real purpose from the start on Centre Court on Monday, showing the ultimate respect for the threat posed by an opponent she knows better than any other.

Venus had progressed more smoothly through to the last 16, having won three rounds without dropping a set. And the 16th seed soon got a foothold in the match, breaking back to level at 2-2. Yet it was Serena who always had the edge and her break to take a 3-2 lead proved sufficient to take the opening set.

Serena’s serve was functioning at an extremely high level throughout, hitting 10 aces and requiring Venus to be rock-solid on her own serve to simply stay in the match. Like her sister, a five-time Wimbledon champion, Venus battled well to keep the second set on serve until 3-3. But then she could hang on no longer. After saving two break points, Venus succumbed on the third with a double fault. And two games later she was broken to love with a backhand sent long as Serena cruised through to take on either familiar foe Victoria Azarenka or up-and-coming Swiss Belinda Bencic in the quarterfinals.

The lack of a celebration from Serena and the warm embrace at the net showed the complexities that the contest involves for both players. But Serena handled both the occasion and the match expertly on Monday, and her steely focus keeps her on course to become the first player since Steffi Graf in 1988 to win all four Grand Slams in a single year.