The impish Irish winger certainly played his part as his loan team pushed the Premiership champions all the way in the fifth round at Stamford Bridge.
And it could have been even better for the 21-year-old as the League One title contenders stunned Jose Mourinho's men in the first half.
Yeatesy could almost see the headlines being written as he connected sweetly with a shot across keeper Carlo Cudicini only for the effort to bounce back to safety off the inside of the post.
Undetered, the Us soon took the lead as Ricardo Carvalho slid Richard Garcia's cross into his own net as the FA Cup favourites were rattled at the Bridge.
Yeatesy's marker Paulo Ferreira bagged Chelsea's equaliser after 39 minutes and the home side brought on the big guns for the second half as Frank Lampard, Joe Cole and Hernan Crespo entered the fray.
Yeatesy was substituted with 15 minutes left and Cole eventually broke Colchester hearts, putting Chelsea ahead four minutes later before curling home for 3-1 in injury time.
"If that shot had gone in it could have been a different story," said Yeatesy. "I could have been a hero.
"I hit it well, I don't think I could have done more really - you normally see those shots go in off the inside of the post rather than bounce back into play.
"It was still a magnificent occasion for everyone at the club. We spoke about what we would do all week and we managed to produce a performance on the day.
"We showed that we are a good side playing good football and we should be proud of ourselves. A lot of Premiership teams have gone to Chelsea this season and not played as well as us."
Yeatesy looked to have the beating of Ferreira and the right-back was booked for a reckless lunge that left our man limping in the first half.
"My leg's mashed up!" added a typically buoyant Yeatesy on Monday. "But you know me - I'm always a bit of a moaner anyway!
"I thought I did well against him, beat him a few times and got some crosses in.
"He's a good right-back, very experienced and you always want to test yourself against those type of players. I've always been confident in my own ability and I don't think I looked too far out of place."
It's back to reality for the Dubliner and Colchester on Saturday as they travel to Barnsley in League One.
Phil Parkinson's men have lost just three in 25 games and are four points behind table-topping Southend with two games in hand.
"Things have been going well and we just have to maintain it now," added Yeatesy. "Every game is massive for us between now and the end of the season and we have to take the confidence from that Chelsea performance into those matches."
Mark Yeates reflected on Colchester's courageous FA Cup display at Chelsea and sighed: "I could have been a hero."