The 20-year-old agreed a two-and-a-half-year contract extension with the Sky Blues on Tuesday.
Pressley has admitted that he has been impressed with Thomas during his time at the club.
"He's an outstanding young player. I think he can play at the very top in the Premier League," Pressley told BBC Coventry & Warwickshire.
"Prior to myself arriving, a lot of people had spoken to me about Conor. I could see his qualities in possession were very good.
"He has a good understanding of the game and he's a good example off the pitch too. Even on his days off this week, he's still been in working on his game."
Thomas has made 61 appearances for Coventry in all competitions.