Jose Mourinho was impressed with the way Colchester forced Chelsea to work hard for their 3-1 FA Cup win.
Mourinho was impressed by his opposite number Phil Parkinson
The League One side took the lead at Stamford Bridge before Mourinho's Premiership champions came back to book their place in the sixth round draw.
"They should go home proud of what they did." Mourinho said. "They played with courage. They were not afraid of us.
"They came to win, not to draw 0-0, and their crowd was unbelievable," added the Chelsea manager.
"They believed it was possible. This is the only country in the world where that would happen."
Mourinho was equally generous in his praise for his opposite number Phil Parkinson.
"They also have a good manager and maybe in a few years they will come to Stamford Bridge in the Premier League. You never know."
Joe Cole paid his own tribute to Colchester after coming off the bench to help Chelsea battle back from a goal down.
Cole, who scored twice, said: "They showed they were right up for it and they gave us a good game.
"It was always going to take a bit of time to settle down. We did that a little bit better in the second half.
"I enjoyed the two goals but the main thing was that we got the job done and we have not got a replay to go to."
Mourinho was unhappy with his side's defending in their first match since losing 3-0 to Middlesbrough.
"You are never happy when players don't play 100 per cent," he said. "But our left-back is not a left-back and Paulo Ferreira was playing his first game in many weeks."
Cole saw the win as an important first step ahead of Chelsea's Champions League quarter-final against Barcelona on Wednesday.
"This is a very important week for us - this game has put us in the last eight of the FA Cup and we have a chance on Wednesday night to take a step towards the last eight of the Champions League.
"Now we will go into the Barcelona game full of confidence. We have got the Middlesbrough defeat out of our system and rested some key players - we are ready for the big one."
Commenting on the state of the Stamford Bridge pitch, which has been criticised by some of Barcelona's players, Mourinho said:
"Sometimes you see beautiful people with no brains, but you see ugly people who are intelligent scientists. Our pitch is a little bit like that.
"It doesn't look great, but the ball rolls and bounces normally."