Kai Martin's 25-yard free-kick was well saved by the Fulham keeper early on and soon after, Lennox Emery's effort went wide after Makise Evans' attempt had been blocked.
But Colchester fell behind after 26 minutes when a shot was converted, after good work by the visitors on the left.
['It's a great opportunity for him': Samson Tovide set to seal move](https://www.gazette-news.co.uk/news/25362325.its-great-opportunity-him-samson-tovide-set-seal-league-one-move/?ref=ial)
However, Elliott Ward's side were back on level terms 12 minutes later through Evans, who was released on the right and found the net.
But equality did not last long as the Fulham left-back raced down that wing and beat keeper Harrison Chamberlain, at his near post.
New signing Kaion Lisbie was introduced at half-time for a trialist and a good early home attack in the second half saw David Nkrumah and Kien Connolly link up well, with the shot saved.
_(Image: CU-FC.COM)_
Lisbie's pass down the left then found Connolly who rounded the keeper but shot wide of the far post.
It was from Lisbie's cross from the left that saw Kien Connolly guide home to make it 2-2, on 51 minutes.
After some excellent build up play, Connolly got his shot away which the keeper stretched up to grab and Nkrumah also saw his effort saved, as Colchester pressed for a third.
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Connolly lifted a shot over the bar but straight after that, Fulham broke and the right winger fired in off the far post, with 15 minutes to go.
A Nukrmah cross ran to Connolly who shot wide and at the other end, Fulham netted again with a header that was ruled offside.
Chamberlain made a good save late on, as Colchester's under-21s were beaten.
Colchester's first Professional Development League game of the season is next Tuesday when they host Wigan Athletic.
Colchester United U21: Harrison Chamberlain, David Nkrumah, Frankie Edwards, Sam Kuffour, Alfie Newby, Trialist A, Max Jolliffe, Lennox Emery, Kai Martin, Kien Connolly, Makise Evans. Subs: Kaion Lisbie, Trialist B, Caiden Lewis.
Colchester United's under-18s lost 5-2 to a Gillingham team managed by former U's boss Joe Dunne.
The U's goals came from James Sasere from the penalty spot after he was fouled and new first year scholar, Josh Adesanya.
Colchester's under-18s begin their league programme at home to Barnsley on Friday, kick-off 2pm.