Vandeweghe will miss Wimbledon due to injury, so Barty will instead partner Victoria Azarenka, with whom she played at the Roland Garros earlier this month.

"When Andy texted me asking me to play, I was a little bit shocked, to be honest," Barty said.

"Obviously I would have loved to have grabbed the opportunity to play with Andy.

"I think it was the hardest decision I have ever had to make as to whether I'm playing an event or not.

"I took some time to think about it, but playing three events is just a little bit too much.

"I had already made a commitment to play with Vika (Azarenka).

"I was very flattered and honoured, and I said to him, 'I think there are some pretty good options out there for you'."

Murray revealed the knockback on his column for the BBC Sport website but said he has been flooded with offers from players past and present who are willing to join forces with him.

The Scot returned to competitive tennis after a five-month injury lay-off in the doubles at the Queen's Club this week and is on the lookout for a partner at Wimbledon, which begins on July 1.

"I would like to play mixed doubles at Wimbledon next month and I have spoken to a couple of players about partnering up," Murray wrote.

"But I've been rejected a couple of times so far – in the nicest possible way, of course!

"One of those people was Ash Barty.

"I asked her during the French Open and she said no because she is already playing in singles and doubles, so didn't want to play in three competitions.

"Of course, I understood that."