The former Aston Villa and Burnley star spent his entire career playing in England before joining MLS side Charlotte FC in January this year.
Westwood's time in the Premier League means he played against stars including Sergio Aguero, Luis Suarez and Eden Hazard, but according to the 33-year-old, nothing could prepare him for going head to head with football GOAT, Messi.
Speaking to Drive on talkSPORT, Westwood said: "There was talk [of Messi joining Inter Miami] in the summer, it had been circling for a while so when it happened everyone was excited.
"Everyone was buzzing for it - the whole country was buzzing for it.
"You watch their games and they've got NBA stars and celebrities going there, it's like a basketball game."
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Westwood faced Messi for the first time in August and the midfielder admits he was overwhelmed by just how good the Argentine superstar actually was.
He explained: "The stadium was full an hour before he even turned up."
"My wife and the kids went to the game, they flew down and they said that even outside of the game he's got 'Messi's Mac and Cheese' and Messi everything. It's all Messi!
"Everytime he touched the ball they're chanting for him and he deserves it, but to be fair, without [Sergio] Busquets they'd be much easier to play against.
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"I thought that Michael Carrick was unbelievable, but again, I thought Busquets was on another level."
Messi grabbed the fourth goal in a 4-0 defeat for Charlotte FC.
"To play against him - I knew he was going to be good, but to be that good was just ridiculous, absolutely ridiculous.
"I was trying to kick him but I couldn't even get near him. He's special, but I don't think he was too happy - he just stared at us the whole time and didn't speak too much English."
Had he landed the kick, though, his bodyguard, who sticks to Messi like glue may have had something to say.
Westwood added: "I've played against some good players but he's on another level. The way he manipulates the ball - like the lads said, you stick your foot out and he just flicks it over you.
"It's like he sees it before it happens, he's a magician."