Roger Federer and Novak Djokovic raced into the third round with straight sets wins but the day was marred by a horrific knee injury to American Bethanie Mattek-Sands, who was carried off on a stretchher during her singles match at Wimbledon on Thursday.
Seven-time champion Federer turned on the style to beat Serbian Dusan Lajovic 7-6(0) 6-3 6-2, while Djokovic needed little more than 90 minutes to beat Wimbledon debutant Adam Pavlasek 6-2 6-2 6-1.
On Court 17, Mattek-Sands was playing Romania's Sorana Cirstea when she appeared to slip as she approached the net at the beginning of the third set, then collapsed awkwardly on to the grass.
Medical personnel arrived and the 32-year-old was treated by doctors on the court for more than 20 minutes, during which time she was given oxygen and an injection.
In a mixed day for the title favourites, German top seed Angelique Kerber battled past Belgium's Kirsten Flipkens 7-5 7-5 in the second round but Czech third seed Karolina Pliskova was dumped out of the tournament.
Pliskova, who came into the championships on the back of a grasscourt title success in Eastbourne, was beaten 3-6 7-5 6-2 by 87th-ranked Slovak Magdalena Rybarikova.
Seven-times champion Roger Federer booked a third round place with a 7-6(0) 6-3 6-2 win over Serbian Dusan Lajovic, ranked 79 in the world.
Second seed Djokovic takes his win-loss record to 18-1 at the championships since 2014.
