The talkSPORT host even made it onto Wednesday night's edition of popular Spanish TV show El Chiringuito de Jugones, as he reacted to the LaLiga outfit's dramatic exit to Liverpool.
Few had given Villarreal much of a hope of progressing to the final in Paris after Liverpool's 2-0 victory in the first leg at Anfield, but you'll only have to ask Juventus and Bayern Munich what happens if you underestimate them.
Whether Liverpool underestimated the hosts is up for debate, but what is certain is that Jurgen Klopp's men were well off their usual pace and sharpness as they saw their 2-0 lead erased in a brilliant first-half display from the Yellow Submarine.
However, the Reds roared back after the break with three goals, with substitute Luis Diaz the game-changer, while the home team finished the game with ten men as their Champions League adventure came to an end.
Cundy riled Villarreal fans and the Spanish press last week with his claim that the manner of Liverpool's first leg win 'disgraced' the rest of European football, claiming that 'it's no wonder they want a Super League'.
To be fair to Jason, it started out quite positive from the talkSPORT host as he praised the Spanish side for their first-half display in the second leg, as they took the game to Liverpool in a way few teams have this season.
But that's where the compliments ended… and it's fair to say his rants were well and truly noticed by our friends in Spain.
"That's what you can do if you actually change your approach to games, when you change your attitude and go at teams," the Sports Bar host began.
"Liverpool showed their vulnerability, and it's the worst I've seen Liverpool in a long time in that first-half, by the way. But, give Villarreal credit, they absolutely took Liverpool to the cleaners.
"Liverpool did not know what was going on. They were all over the place. Defensively, you're talking about players like who are generally calm and collected, but Virgil van Dijk was all over the place, Andy Robertson and Trent Alexander-Arnold - that's what happens when you put teams under pressure and when you can actually force your games onto them.
"And then the half-time whistle goes…"
And it begins.
"What did Unai Emery say at half-time? What do you think he said? Same again? No! I'll tell you what he said - 'sit deep, control the game, try and catch them on the counter'. That's exactly what they tried to do in the first-leg and they had their collar felt.
"I saw the second-half of that game tonight play out exactly the same way as we saw in the first-leg. I'm sorry, but it's shocking from them!
"I don't know what you want me to say. What do you want me to say? Do you want me to give them some credit? The first-half, yeah, well done and well played.
"And they deserve credit for getting there, but when you're there you're there to be shot at, to be criticised, to be judged. I may have been a little harsh with some of the things I said after the first-leg, but I'm absolutely going to stick to it.
"That second-half performance tells me what I said after the first-leg was 100 per cent right!
"On that night what I said was that the rest of Europe and UEFA should be fearful of what they saw. I've just seen this second-half - Villarreal were 2-0 up at half-time, they lost the game 3-2 and had a man sent off! What does that tell you? This is a side that's just got to the semi-final of a Champions League and Liverpool were far superior.
"What we're looking at is a Villarreal side that has somehow bumbled their way to the semi-final. Credit to them as they knocked out Juva and Bayern, brilliant, but when you get there you come up against class like Liverpool, you're going to get your collar felt."
Cundy also hammered Villarreal goalkeeper Geronimo Rulli, saying he was at fault for FOUR of Liverpool's five goals across the two games and that he is not even good enough to be a number two at a Championship club.
Ouch.
"The goalkeeper - he's a shocker, mate," the former Chelsea defender continued.
"I'm sorry, but he was at fault. I've had a look back, I just had to refresh my mind with the first goal that he punched in at Anfield, and he was at fault for four of the five goals in that tie.
"How can you go into a Champions League semi-final with a goalkeeper that isn't good enough to be an understudy in the Championship?
"Honestly. Sam Johnstone [the West Brom and England keeper], there are a lot of clubs after him, he's out of contract, and he's a better goalkeeper than what I've seen tonight and over the two legs.
"Villarreal are a Frankenstein team of former Premier League players and a former Premier League manager, and they did as well as they possibly could have done in the first-half of the second leg.
"But over the three halves that Liverpool dominated, they were just second-rate."
Co-host Jamie O'Hara saw things differently, with the former Tottenham man insisting Villarreal - who boasted three former Spurs players in their squad and one currently on loan from north London - deserved credit and should be proud of their run.
But Cundy wasn't having it.
"You've said they were a disgrace and you're trending all over Europe but, for me, tonight they did themselves proud," said O'Hara.
"They took Liverpool all the way and it took Liverpool to come out in the second-half and play at their absolute peak to get it done.
"Yes, the goalkeeper made some bad mistakes, but Villarreal can be proud of themselves.
"I think you should apologise, because there have been a lot of people upset about it."
He could be waiting a while…