There have been 21 Liverpool and West Ham United double-agents who have represented both the Reds and the Hammers in the English top-flight during the Premier League era. This includes Danny Ings, who will come up against his former club when Arne Slot’s men travel to the London Stadium on Sunday.

Liverpool have ultimately acted as a step up for the likes of Javier Mascherano, Yossi Benayoun and Glen Johnson, while Andy Carroll, Stewart Downing and Joe Cole were among those to be offloaded to West Ham when their Reds careers did not pan out as planned.

But there could have been another two double-agents to add to such a list if a fanciful swap deal had not fallen through back in August 2010.

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If you mention Ryan Babel to supporters, one of the first things that will come to mind is perhaps the ‘Babelcopter’ saga. Having fallen out of favour at Anfield, he spent transfer deadline day that year in a helicopter on his way to London, only for no move to actually materialise.

Said to be joining West Ham, Carlton Cole was lined up to move the other way as part of the swoop. But the Dutchman later posted on Twitter that he was “going nowhere” and was “LFC all the way” as his exit eventually collapsed.

Babel has previously put this down to a miscommunication regarding the terms of his exit when clearing up what really happened years later.

But in an exclusive interview with the ECHO when looking back on the saga, the Dutchman now suggests he was misled as he recalled how devastated club officials were when he refused to join West Ham on a permanent basis - to the extent that he even had to make his own way back to Merseyside rather than return by helicopter!

“So the Babelcopter story. That was an interesting one,” he recalled. “I remember on deadline day, it was very last minute and I think it was with West Ham United.

“They were trying to do a swap deal at that time with Carlton Cole. And it was supposed to be a loan deal. That's what I've been told by my agent. They had brief contact with my agent and, I think we had six hours left to the deadline.

“I was called and had been told to immediately go to the airport because Liverpool representatives would wait for me and then we would go there and fly to London to make the deal happen.

“And as I arrived, I saw a very small, little, two-person helicopter. It was a very small one. And I'd never flown in a helicopter before. That helicopter didn't really look safe!

“But as I had this journey, I was also very active on Twitter, so I was actually tweeting my whole journey. So I describe the moment arriving and what I saw. I was like, ‘Wait, what's going on?’

“You know, I have to go for a medical and everything. And maybe my life is depending on this little thing. I was having a little banter on Twitter with that, with a bit of a story.

“And yeah, in a nutshell, long story short, we arrived, me and one of the Liverpool sports directors. We arrived and we were then picked up by a driver from West Ham.

“And then he was like, ‘Yeah, you're going to sign a five year deal and then we are going to sign Carlton Cole.’ And I was like, ‘Wait, wait, wait a minute. What do you mean five years? I thought it was a loan deal?’

“He was like, ‘No, no, it will be a swap deal.’ And so I called my agent and he said, ‘No, no, definitely a loan deal. We didn't discuss anything about five years. Put him on the phone.’

“And then they had been talking and I could tell that the conversation didn't end well. And then the transfer basically fell through. I could see the disappointment on the sports director’s face.

“He made some calls saying, ‘Yeah, the player doesn't want to sign.’ And so he blamed it on me basically that I didn't want to keep my end of the deal. But I was like, ‘Well, I'm sorry, but that was not what we discussed, right? Was a loan deal.’

“And then he was like, ‘Yeah, no, I thought it would be better for you to sign and, you know, you can develop and we have a clause to buy you back.’ And I was like, ‘Well, my agent didn't tell me that.

“So then he was disappointed. And rather than flying back to Liverpool, he put me on the train. So I had to go back on the train to Liverpool!”

Even now, Babel has no regrets about snubbing a move to West Ham despite his struggles at Liverpool at the time.

“No (regrets), because I still had so much belief that I could do it for Liverpool,” he explained. “Thinking about it, it was just really the people managing the club. They didn't really do a great job by managing the players the right way.

“When Benitez left and I remember also I think there were a few changes in the directors, I had some hope because you had Roy Hodgson coming in. But yeah, it was kind of already a little bit too late because Roy Hodgson was under pressure really quickly.

“He was trying to build on the more experienced players rather than have time to work with the younger players. And I was one of the younger players still. So yeah, it didn't turn around my Liverpool career.

Babel had actually been the subject of interest the previous January when Liverpool rejected a bid from Birmingham City. He was aware of the interest, and left frustrated off the back of limited game time at Anfield under Rafa Benitez.

“Yeah, there were many teams that were trying to sign me and Liverpool was blocking it at that time,” he said. “That was also really confusing because if I didn't really get play time, why wasn't I allowed to leave or at least go on loan?

“So yeah, I was aware of the Birmingham interest at the time. Absolutely. We did try to understand the reason of Liverpool at that time. Not giving me a chance to find luck elsewhere. And the constant feedback was that I was important to Liverpool.”

Babel would eventually leave Liverpool for Hoffenheim in January 2011, with his exit contributing to bumper deadline day at Anfield. Departing in an £8m move to the Bundesliga outfit, Fernando Torres would follow him out the exit door in a £50m switch to Chelsea as the Reds reinvested the funds to bring in Luis Suarez for £22.7m and Andy Carroll for £35m.

With Sir Kenny Dalglish having only just been appointed caretaker manager at Liverpool at the time, the Dutchman recalls how the Reds legend told him he would still have a future at the club if his move to Hoffenheim did not go through.

And in hindsight, given Liverpool’s own transfer misfires in the subsequent years, Babel admits he does wish he had instead chosen to stay at Anfield with the forward considering his decision to leave one of the only regrets of his career.

“I had a good relationship with Kenny Dalglish,” he said. “Kenny Dalglish came in as an intern. I remember at that time he was not the official manager yet.

“I was already in talks with the team in Germany and he said, ‘Look, you know, if for some reason you end up not going, I promise you to work with you and give you your chances.’

“I think I only worked two weeks or something under Kenny Dalglish, and then I left to go to Germany.

“If I analyse, I would say maybe it would have been a better decision to stay at Liverpool with all the changes. If I knew beforehand that these changes would happen, maybe it would have increased my play-time at Liverpool.

“I remember signings like (Stewart) Downing and a lot of these players who eventually didn't really… they were not able to put Liverpool back on the map. I think watching back, maybe it could have been for new opportunities for myself, but yeah, it was already too late.

“I think the one of the most important regrets is, of course, leaving the way I did. Yeah, I think that was one of the regrets overall. Not just Liverpool regret, but my football regret for sure.”

Ryan Babel was speaking to the ECHO to promote his short film about his career, ‘After the Whistle’, which is out now on Ryan Babel’s YouTube channel following his retirement from football earlier this year.