Relieved Djokovic advances after shoulder injury scare

"It was obviously a scary fall, I tried to land on my left arm.  I basically had a strong impact on the shoulder.  When I stood up, you know, I felt that click or pop.

"I feared it might be a dislocated shoulder or joint problem. But luckily for me it was only an impact that had a minor effect on the joint and the muscles around, but no significant damage," he said after a post-match scan eased his worries.

Djokovic slipped as he chased a shot off the Simon racquet late in the match. He rolled twice and grimaced in pain, getting treatment on the sidelines from a physiotherapist and painkillers from a doctor before finishing off the last four games for the victory.

The Serb won in just over two hours with seven aces, 31 winners and seven breaks of serve.

"In the important moments, I played well," he added after winning his 41st Wimbledon contest. "It was up and down throughout the match."

Djokovic next faces 14th seed Jo-Wilfried Tsonga after the Frenchman beat Taiwan's Jimmy Wang 6-2, 6-2, 7-5.

South African Kevin Anderson put out Italian Fabio Fognini 4-6, 6-4, 2-6, 6-2, 6-1 after the 16th seeded Italian was fined 27,000 dollars for protests and arguments with the chair umpire during his first-round match.

2013 semi-finalist Jerzy Janowicz put out former champion Lleyton Hewitt, winning 7-5, 6-4, 6-7 (7-9), 4-6, 6-3 in a second-round match left over from Thursday.               

Hewitt, 33, was playing in his 42nd five-set match at the grand slams, edging ahead of Andre Agassi.

Women's second seed Li Na lost to Czech Barbora Zahlavova Strycova 7-6 (7-5), 7-6 (7-5) with the Chinese admitting she made a tactical error by not playing a warm-up event on grass.

She said that past experience in Britain had meant only rain, with no chance to train, so she skipped the entire process. "I made the wrong decision, I need to play some matches before the big one."

It was the third time in four editions that China's top female sporting icon had failed to pass the second round. It came less than a month after she was beaten in the Roland Garros first round, the grand slam the 32-year-old won three years ago.

2012 finalist Agnieszka Radwanska, seeded fourth, crushed Michelle Larcher De Brito 6-2, 6-0.

2011 champion Czech Petra Kvitova ended the run of five-time winner Venus Williams 5-7, 7-6 (7-2), 7-5, preventing the 34-year-old moving into joint third place in all-time Wimbledon wins (74).

Czech Lucie Safarova knocked out Australian Open finalist and 10th seed Dominika Cibulkova 6-4, 6-2 while 16th seed Caroline Wozniacki beat Croatian teenager Ana Konjuh 6-3, 6-0.

French Open finalist Simona Halep, the third seed, played a delayed second-round match, beating Lesia Tsurenko of the Ukraine 6-3, 4-6, 6-4.