Like Sinclair, Colwill came through Chelsea's academy system and finished the season a Europa Conference League winner.
Reflecting on victory over Real Betis, Sinclair told Tribalfootball.com: "Yeah, he's been terrific. You know, another young player that's come through who's shown that he's of the level. You know, he's now rightly so an England international as well.
"But I did fear for, I think it was (Benoit) Badiashile who took his place in the team, who has not had a lot of football recently and has been known to have the odd mistakes in his game. In such a big game, I did fear, but I thought he was fantastic on the day, especially with his distribution, the balls that he was punching into midfield areas for players to receive, I thought was excellent.
"And he obviously gave that natural left-sided balance that Colwill normally gives anyway. So it was a brilliant bit of selection by the Chelsea head coach (Enzo Maresca)."
- Frank Sinclair was speaking to Tribalfootball.com on behalf of William Hill