With her heart racing as she stood two points from defeat in her third round match at Wimbledon, Serena Williams looked in serious danger of missing out on a 26th on-court date with older sister Venus.

For a fleeting second, the American even contemplated finding “a dance class” while she “hung around to watch Venus play” as brave Brit Heather Watson looked like she would deny the sisters a chance to renew their Wimbledon rivalry by toppling the world number one.

Those dance classes were soon a distant memory as US, Australian and French Open champion Serena kept alive her dreams of completing the “Serena Slam” by setting up a fifth All England Club showdown with her sister.

A contest that will feature two women who between them have hoisted the Rosewater Dish 10 times since 2000 has the potential to be a classic but could very well turn out to be the ultimate anti-climax as has been the case in many of their previous meetings.

Serena leads their overall head-to-head 14-11, and is 3-2 at the grasscourt major having won their last grand slam meeting in straight sets in the 2009 Wimbledon final.

Not everyone was sure if Serena was engaging in some mind games when she declared Venus was “in better form than I am and I think she has a little bit of an advantage going into that match.

“I’m playing the toughest player I’ve ever played in women’s tennis. That’s never fun.”

Five-times champion Venus, however, took that observation with a pinch of salt.

“There’s no easy points against Serena. No matter how Serena’s playing, she knows how to win,” said 16th seed Venus, who a year ago snapped a run of five successive losses to her sister in their last meeting in Montreal.

What is true is that Venus’s progress has been drama free and her run includes a 6-0 6-0 walloping of the unfortunate Madison Brengle in the opening round.