Milos Raonic of Canada hits a return to David Goffin of Belgium during their men's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Raonic won 3-2. (Xinhua/Ye Pingfan)

Serena Williams of the hits a return to Svetlana Kuznetsova of during their women's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Serena Williams won 2-0. (Xinhua/Han Yan)

Milos Raonic of Canada hits a return to David Goffin of Belgium during their men's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Raonic won 3-2. (Xinhua/Ye Pingfan)

Serena Williams of the United States hits a return to Svetlana Kuznetsova of Russia during their women's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Serena Williams won 2-0. (Xinhua/Han Yan)

Milos Raonic of Canada hits a return to David Goffin of Belgium during their men's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Raonic won 3-2. (Xinhua/Ye Pingfan)

Milos Raonic of Canada hits a return to David Goffin of Belgium during their men's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Raonic won 3-2. (Xinhua/Ye Pingfan)

Milos Raonic of Canada serves to David Goffin of Belgium during their men's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Raonic won 3-2. (Xinhua/Ye Pingfan)

Milos Raonic of Canada hits a return to David Goffin of Belgium during their men's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Raonic won 3-2. (Xinhua/Ye Pingfan)

David Goffin of Belgium hits a return to Milos Raonic of Canada during their men's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. David Goffin lost the match 2-3. (Xinhua/Ye Pingfan)

David Goffin of Belgium hits a return to Milos Raonic of Canada during their men's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. David Goffin lost the match 2-3. (Xinhua/Ye Pingfan) 10

Andy Murray of Britain celebrates his victory over Nick Kyrgios of Australia during their men's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Murray won 3-0. (Xinhua/Han Yan) 11

Andy Murray of Britain hits a return to Nick Kyrgios of Australia during their men's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Murray won 3-0. (Xinhua/Han Yan) 12

Andy Murray of Britain celebrates his victory over Nick Kyrgios of Australia during their men's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Murray won 3-0. (Xinhua/Han Yan) 13

Andy Murray of Britain hits a return to Nick Kyrgios of Australia during their men's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Murray won 3-0. (Xinhua/Han Yan) 14

Andy Murray of Britain celebrates scoring during the men's singles fourth round match against Nick Kyrgios of Australia at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Murray won 3-0. (Xinhua/Han Yan) 15

Andy Murray of Britain hits a return to Nick Kyrgios of Australia during their men's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Murray won 3-0. (Xinhua/Han Yan) 16

Nick Kyrgios of Australia hits a return to Andy Murray of Britain during their men's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Kyrgios lost the match 0-3. (Xinhua/Han Yan) 17

Nick Kyrgios of Australia hits a return to Andy Murray of Britain during their men's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Kyrgios lost the match 0-3. (Xinhua/Han Yan) 18

Venus Williams of the United States hits a return to Carla Suarez Navarro of during their women's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Venus Williams won 2-0. (Xinhua/Han Yan) 19

Nick Kyrgios of Australia hits a return to Andy Murray of Britain during their men's singles fourth round match at the Wimbledon Tennis Championships in London, Britain on July 4, 2016. Kyrgios lost the match 0-3. (Xinhua/Han Yan) 20