Both played in the Australian Open which required them to be fully vaccinated. According to this source that listed all of the competitors who withdrew, all of them received the experimental injection.
Rafael Nadal recently lost his match in Palm Desert after having chest pain.

Other athletes have recently had unusual health issues, including three professional cyclists who recently suffered cardiac-related events, and two of them died. A 23-year old Romanian water polo player died during a game while suffering chest pains.

The tennis world has been shocked this week at the Miami Open.

Fans witnessed an unprecedented number of withdrawals/retirements from the tournament at Hard Rock Stadium.

The most shocking moments of the event occurred when both favorites, Italian Jannik Sinner and Spaniard Paula Badosa retired from their quarterfinal contests on the same day.

Yahoo Sport reported:

Soon to be World No.3, Badosa was in tears as she was forced to bow out of the quarter-final after not feeling well against American Jessica Pegula.

On Monday, Badosa admitted she wasn't sure if she could compete in her fourth round match that she subsequently won.

However, the Spaniard was in obvious discomfort when she retired sick at 4-1 in unfortunate circumstances for the in-form star.

On the men's side of the draw, Italian phenom Sinner was also forced to retire against World No.103 Francisco Cerundolo.