Garnacho, who made the £40M move to West London in the summer, had been a controversial figure in the Premier League for some time.
The winger shared snaps from his holiday to Ibiza earlier this year, which included a picture of him wearing Marcus Rashford's Aston Villa shirt as he starred away from Manchester United, a club he was in a feud with at the time.
Keep an eye on Garnacho
However, the Argentina international has so far changed his way at Chelsea and looks to have become a whole new player under manager Enzo Maresca.
Despite this, Given believes Garnacho is one to keep an eye on as he believes his attitude is toxic as he spoke to Premier Sports.
“I think he rubs a lot of people up the wrong way, including myself. And this is probably me being a dinosaur, the way he's turned up to one side and a chain hanging out, his attitude.”
“His attitude when he gets taken off, he's throwing his jumper, he's kicking water bottles. He's a young player, he has to get his knuckle down, and focus on his career.
“You see (Robert) Lewandowski heading off the bus tonight, he's got no headphones, he's got no mad hats on, he's professional, he's getting ready for the game.”
Having fallen out of favour under United boss Ruben Amorim, Garnacho has thrived under Maresca, who has helped him to four goal contributions in 11 appearances so far.
Maresca happy to see Garnacho thrive
Maresca revealed how happy he is with Garnacho’s progress earlier this month as he adapts to the side.
"He arrived here from another club where he was not training 100 per cent so his physical condition was not good.
"Slowly, slowly, now it's better. He's doing very well on the ball, but he's doing very, very well off the ball. He knows that to play with us he has to be good on the ball and off the ball otherwise he's not going to play. We are very happy with him at this moment."