Wimbledon defended shunting top women players onto the outside courts on "Manic Monday", saying the big four of men's tennis were the marquee matches demanded by broadcasters and spectators.
Andy Murray and Roger Federer's matches were put on the 15 000-seater Centre Court, with Rafael Nadal and Novak Djokovic on Court One on the second Monday, when all the men's and women's last-16 matches are played on the same day.
Former champion Venus Williams made it on the Centre Court bill, while British home favourite Johanna Konta rounded out the order of play on Court One, which holds 11 000.
That meant world number one Angelique Kerber was out on the 4,000-seater Court Two facing fellow former runner-up Garbine Muguruza, followed by former world number one Victoria Azarenka against world number two Simona Halep.
On the 2,000-seater Court Three, former Wimbledon finalist Agnieszka Radwanska faced two-time Grand Slam champion Svetlana Kuznetsova, followed by ex-world number one Caroline Wozniacki.
Meanwhile the new French Open champion Jelena Ostapenko was on the 1,000-seater Court 12 show court.
All England Club chief executive Richard Lewis said the nature of Wimbledon's Manic Monday -- unique among the four Grand Slams in that all last-16 matches are played on the same day -- meant big name players would not get on the main courts.
"You've got four of the all-time great male players: Rafa, Roger Novak and Andy. You're left with some difficult choices," he told reporters.
"We absolutely respect that Angelique is number one in the world, Muguruza is a former finalist, a Grand Slam winner. It was a tough decision. But we are spoilt for choice. There are matches on Courts Two and Three today that would grace Centre on any other day."
The decision to make five-time Wimbledon winner Williams the only big-name woman to play on Centre Court was a unanimous one, he said.
"We felt that a former champion and one of the all-time great players deserved to be on Centre Court. Venus has played on Court One three times so it felt like the right time," said Lewis.
"It was a unanimous view that Venus deserved to be on Centre in respect of what she's done in her career."
Defending the Manic Monday format, Lewis said it gave fans with cheaper outside court tickets the chance to see bigger-name players in action.
"It's a great day. A former player said to me they think it's the best day in the tennis annual calendar because there's so many great matches, fans are spoilt for choice," he said.