Manager Ted Fenton's first squad had numbered 28 part-time professionals, but this was reduced to just 17 for the 1947-48 campaign. Quantity was replaced by quality with the likes of Bob Curry, Bob Allen, Arthur Turner, Harry Bearryman, Digger Kettle, Dennis Hillman and Len Cater to name a few. At this time, Colchester United were on the verge of being put on the football map via a truly magnificent run in the FA Cup.
The competition got off to a rather unspectacular start for United as they crept home 3-2 against neighbours Chelmsford in the Fourth Qualifying Round watched by a Layer Road crowd of 10,396. It was the second year running that The U's had reached the First Round Proper, they had been soundly beaten 5-0 by Reading twelve months earlier, and 8,574 fans held on nervously as Colchester edged out Banbury Spencer by a slim 2-1 margin.
Wrexham, of the Third Division North were the next visitors to Layer Road and they were duly dispatched by a Bob Curry goal with both sides missing penalties. Once again, over 10,000 fans crammed into Layer Road. Ironically it was First DivisionHuddersfield, the club that had inspired United's own team strip, who were next to be put to the sword. The national press were making big things of little old Colchester and Fenton courted the publicity. He watched Huddersfield a couple of times before the tie and declared to the media that he had come up with a plan to beat them. This became known countrywide as 'The F-plan'. Both teams changed colours, Huddersfield to red and The U's to blue. Huddersfield struggled to adapt to the cramped surroundings and on 70 minutes Allen's free-kick was only parried by the visiting keeper and U's captain Bob Curry stabbed home the rebound. It was the first time that a non-League side had beaten a First Division club. The 16,000 crowd that witnessed that famous victory could easily have been trebled for the Fourth Round tie with Second DivisionBradford Park Avenue had Layer Road been able to accommodate them.
United didn't disappoint, although their opponents were more wary of Colchester's growing reputation. Indeed Bradford took the lead only for Curry to net twice before the visitors equalised on the stroke of half-time. Fred Cutting stroked in United's third to send the home crowd into delirium and Fenton was chaired off the pitch at the final whistle. The Fifth Round draw was awaited with bated breath.
Blackpool, Stanley Matthews et al., were drawn out to host Fenton's Cup heroes. The effects of War were still evident with fuel rationing and just 36 hours before 52 coaches were due to set off for the north-west coast the Ministry of Transport reinforced their restriction on fuel usage. Over 40 coaches had to be cancelled and as a result U's fans had to travel by train. This meant, however, that they would arrive in Blackpool in the early hours on the morning of the match. This did not deter the hardy band of fans and the West Lancashire Post reported:
"The peace of Blackpool was shattered at dawn today by thousands of Colchester fans, waving rattles, ringing bells, blowing trumpets and shouting 'Up The U's'. Not since pre-War Illumination weekends has there been such an invasion as stormed our streets from 4 o'clock this morning."
The support was good natured but the home side powered to a 5-0 victory in front of a 30,000 sell-out. Colchester United were now everybody's favourite non-League side. FA Cup success had an effect on League form and United finished fourth - nine points adrift of champions Merthyr Tydfil. They also reached the Southern League Cup Final but time ran out for the match to be played. It was inevitable after all the national publicity that Ted Fenton would be sought after. When the opportunity came to become assistant manager at West Ham in the summer of 1948, Fenton could not refuse.