Andy Murray says there are "more important things than tennis" after three people were killed and another three injured in attacks in Nottingham.
Murray said he did not know if play would be suspended at the Nottingham Open, but it went ahead with the Briton winning his first-round match.
"It was obviously shocking when I woke up this morning," said Murray, 36.
"When I was going down to breakfast a few messages on our team chat came up.
"We are staying in the city centre and had been out for dinner last night and walking around those areas. You never expect something like that to happen."
The three-time Grand Slam champion added: "Really shocking and obviously heartbreaking for the victims and the people involved.
"We were talking about it this morning, saying that we didn't know if the tournament was going to be suspended for the day because there are way more important things than a tennis event."
A man, 31, was Tasered by police before being arrested on suspicion of murder, after the attacks began at 04:00 BST on Tuesday.
Murray, who won the Surbiton Trophy on Sunday and is building up to Wimbledon, earned a comfortable 6-3 6-4 victory over Belgium's Joris de Loore.