The Chelsea academy graduate turned midfield star is on the brink of ending his 18-year spell at the club to sign for Premier League rivals Manchester United.
After failing to agree a new deal with Chelsea with his current one entering its final year and rejecting three bids from the Red Devils, the Blues have agreed to sell Mount for £55m plus £5m worth of add-ons.
One person gutted to see Mount move on is former Chelsea player, lifelong fan and talkSPORT Sports Bar co-host Cundy.
"I've watched Mase and I've followed his career. I do Chelsea TV so I've been lucky enough to document his career over the years," Cundy explained.
"Watched him. he went to Vitesse, was an absolute rising star over there. Come back, went to Derby, a rising star. He's done what everyone else at Chelsea football club and the academy [thought he'd do].
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"They all predicted this. Something went catastrophically wrong with the club between him [and them]. I've got no idea how it happened.
"What I'm saying is he's developed into a fine young footballer."
When asked whether it was bad business from Chelsea letting go of Mount by co-host Jamie O'Hara, Cundy said: "Well I don't think there was any alternative unfortunately."
O'Hara then questioned how the Blues had found themselves in a position where they give up homegrown talent to rivals, Cundy gave his take on why he thinks his club are losing Mount.
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"That is a very good question," he said. "The fact he can win player of the year twice, he's loved and adored by the fans, I have no idea how it kind of got this position.
"If you go back to when we won the Champions League in '21, he was very much an integral part of that side.
"Since then, the club has been rocked by so many things. People say 'oh it's excuses', it's not excuses. What happened at Chelsea football club is unprecedented."
Former owner Abramovich's departure in 2022 following Russia's invasion of Ukraine lead to the club being taken over by Los Angeles Dodgers owner Todd Boehly for £4.25billion.
From start to finish, the transition has been rocky for the Blues, culminating in a 12th place finish in the Premier League last season and a lowest ever Premier League points total.
And Cundy believes it isn't surprising Chelsea are now losing some of their talent as a result of last year's chaos.
"I think what we're watching with Mason leaving now, is a little bit of fall out between Roman [Abramovich] leaving, the sanctions that came in, [Todd] Boehly taking over.
"Looking back, I'm not so sure both sides have come out of it particularly well."