Jurgen Klopp and Andy Robertson have discussed their experiences of mental health challenges - revealing anguish over loved relatives not living to witness their greatest achievements.

Liverpool manager Klopp and his star left-back have taken part in the #SoundOfSupport series for the Heads Up campaign, which Prince William, the Duke of Cambridge, is spearheading.

Scotland international Robertson, now a Champions League and Premier League winner with the Reds, recalled the difficulties he encountered as a teenager being released by Celtic and the struggle of losing his aunt, a prominent supporter of his when growing up.

Speaking of his Celtic exit, Robertson said: "I was a normal 15-year-old lad so there were probably a few tears but my mum and dad got me my favourite curry that night.

"My auntie came up to the house and she told Mum: 'I'm telling you, he'll make it as a footballer.' And that's something that's always stayed with me.

"When I was at Dundee United, on Christmas Day, sadly she passed away. She was one that always believed I was something special even when probably nobody believed it when I was younger.

"But that is something that does bug me a little bit, that she's not seen me lifting the Champions League, lifting the Premier League and things like that."

That prompted Klopp to recall a similar experience when he lost his father shortly before becoming a manager.

"My dad never saw me as a manager. He died four months before I became a manager," the former Borussia Dortmund boss said.

"He pushed me through my [playing] career pretty much, with really harsh criticism and stuff like this, but now my real career, he never saw. That's hard from time to time."

The series is attempting to use the reach of football to get people to open up about their mental health, an issue particularly prominent over the past few months with the coronavirus pandemic consigning people to spend large periods of time at their homes.

"Uncertain I think, for all of us," Robertson said when asked about how he coped with lockdown.

"We have parents that are older, we have family that are in the so-called bracket of high risk. 

"I think football kind of took a step to one side, but we were all wanting the season to end."

Klopp replied: "There were moments in the lockdown when we thought it is a proper setback from all of our dreams.

"So it was a setback but it was a setback for all of us together, and we could calm each other down.

"[It] helps if you don't feel all the burden on your own shoulders. If you have a group of friends or a group of colleagues and you can create an atmosphere like this, that helps.

"I think there is no problem big enough or small enough that you cannot talk about it."

Robertson spoke about how his own experiences were exacerbated once he made it in the game.

"When I started making it professional that's when I struggled the most," he said.

"I was down in Hull on my own and people thought 'okay, he's a Premier League footballer, he's playing for Hull, he's getting a good wage' so then people would stop asking 'how are you?'. I used to be one who blocked everything up and thought 'my problems are my problems'.

"Now I feel so much better. I remember speaking to [my partner] Rach a year ago about something daft, something that was playing on my mind and after a 10-minute conversation with her I felt everything was off [my shoulders] and thought, 'yeah, I should do this a bit more often'."

Manchester City duo Ilkay Gundogan and Phil Foden, and Manchester United midfielder Jesse Lingard, appeared in separate videos for the campaign.

Germany international Gundogan spoke about the feeling of isolation during lockdown away from his family.

"For me growing up, the most important thing was always family. They were kind of like the psychologists for myself. [Now] I am in a different country, I don't know many people apart from the people from the club," he said.

"I have one friend over here who I saw during lockdown. The fact that I have spent a lot of time on my own and without family and friends during lockdown just showed me how important it is to have your loved ones close to you."

Lingard, who appeared alongside TV and radio presenter Maya Jama, revealed family issues had affected his performances on the pitch.

"Last season, I was going through some things off the field with my family so it was difficult for me to perform on the field," Lingard said.

"I'm very family orientated and my mum was going through some things last year with depression. So, in the meantime, I had to look after my little brother and sister who are 12 and 15. I was still performing at the same time.

"You just get to that point where you're like, I've got to actually say something. I spoke to my family and stuff like that. It felt so much better."