The top-ranked Alcaraz beat No. 5 Fritz, 6-4, 6-4 in the Japan Open final for his eighth singles title this year.

The Wimbledon champion defeated Camila Osorio via retirement while Alcaraz rallied to beat Casper Ruud in three sets.

In other matches, Eva Lys upset Elena Rybakina, and Paula Badosa and Barbora Krejcikova both retired injured.

Musetti was annoyed by coughing in the crowd during his win against Giovanni Mpetshi Perricard.

The top seed kicked off her Beijing campaign with a 6-0, 6-3 victory over Yuan Yue Saturday.

The defending champion is keen to keep feeling the love in Beijing.

"When I planted the ankle, I was worried, because it didn't feel good at the beginning," the world No. 1 said after his 6-4, 6-2 win over Sebastian Baez.

The letter calls for a greater share of revenues, contributions to pension, health and maternity benefits, and a greater say via a new player council.

Tiafoe lost to qualifier Marton Fucsovics in the first round of the Japan Open.

Djokovic once called the Croat, the first coach to lead three countries to Davis Cup glory, his "tennis father."