Murray could learn from mother
Andy Murray has revealed he would consider being coached by his mother Judy later in his career.
The world number three will take on Denis Istomin on Tuesday for a place in the quarter-finals of the US Open.
The Uzbek is notable for being the only male player at the top level of the game to be coached solely by his mother.
Murray was coached by Judy when he was younger and she remains an important part of his support team.
Formerly the national coach for Scotland, Judy now works with Britain's leading women and girls and is the Fed Cup captain.
Ivan Lendl has said in the past he would like to coach Murray for the rest of his career but, asked whether he could imagine being coached by his mother again, the Scot told reporters: "I wouldn't rule it out.
"It's not something I've thought about too much. But maybe when I start to come to the end of my career, it might be something that would be nice to do.
"Tactically she's very good. She scouts a lot of matches and likes to watch videos of other players.
"My mum coached me and my brother until 11, 12 years old. Then I worked with Leon (Smith) for a long time. But my mum still helped.
"Probably up until I was about 17 or 18, she always took an interest in who I was working with and what I was working on because she understands tennis and she's a coach herself.
"My mum's never played in a grand slam final, but she's sat through them. She would understand the sort of nerves and the pressure that I'm feeling.
"In terms of tactics, it basically depends how much someone cares, if they really want to go into the tactics, look at videos, get stats. And she enjoys that part of it. So there's no reason why she couldn't help or give tactics in a match."
Klaudiya Istomina, a keen player herself, introduced her son to tennis and has coached him throughout his career.
Istomin said: "We have a good relationship and we understand each other very well. She has known me since I was born!
"She always tries to help me with everything, not just tennis, normal life as well.
"She gives me good words to improve my tennis, my life, everything. I'm happy to be coached by my mum."
He concedes it does have its downsides, though, such as not being able to answer back.
Gesturing to indicate a clip round the back of the head, Istomin said: "I try to say my way as well. Sometimes I say, ' I can't feel the ball like you say'.
"She says: 'Do it like this and you will be okay. Just listen to me.' She's normally right. I will try to fight but in the end I give in."
The relationship also has its challenges from a practical point of view.
"I don't think the other players think it is unusual," said Istomin. "But it's tough for the other players to travel with female coaches.
"Even to go into the locker room before the match and talk - they cannot do it. I always go outside and start to talk before the match with my mum. So it's also tough for me as well."
Istomin is ranked 65th in the world and is through to the fourth round at a grand slam for only the second time after beating Andreas Seppi in five sets on Sunday.
Murray has won their only previous meeting, in Brisbane this year, but Istomin is a dangerous big-hitter who took a set off Novak Djokovic in Montreal last month.
The Scot said: "There's not loads of people that get coached by their parents. A lot of them do from a young age, but not so much when they're on the tour.
"Obviously it works for him. Technically he's very sound. He's a good player. He hits the ball very flat. He served extremely well I think in his match (against Seppi). I saw some of the stats at the end.
"He's played well. He had a very good match with Novak in Montreal. He's had some good wins this week as well."