THE Linnets were given a stark reminder of the gulf between the Blue Square Premier and the Southern League as they made a dignified exit from the FA Trophy.
Woeful defending on the Linnets' part, allied to clinical finishing from Jimmy Quinn's side, highlighted the gap in class between the two teams despite Lynn outplaying their hosts in-between the two penalty boxes.
The final scoreline flattered the U's somewhat, but the brave Walks outfit can use this experience as a springboard for what is required in the future.
Both managers made a number of changes to their starting line-ups, which surprisingly saw the leading scorers of both sides on the bench.
U's boss Jimmy Quinn preferred Lee Boylan to Scott Rendell as a partner for Leo Fortune-West, while Linnets chief Keith Webb started John Turner against his former club, leaving the unlucky Danny Bloomfield as a substitute.
With influential skipper Mark Warren ruled out with flu, the versatile Mark Camm partnered Greg Crane in the heart of the defence and there were returns for Ben Chapman, Steve Melton and Phil Mulryne at the expense of Michael Frew (flu), Greg Lake and Dan Buhlemann from the side that started against Clevedon.
Lynn made a sprightly start, with Joe Francis, who gave the United defence a torrid afternoon down the left, the chief threat.
But Lynn's makeshift defence always looked vulnerable at set-pieces and the opening goal in the seventh minute came out of nothing when Lynn failed to clear a dangerous free-kick and Fortune-West and Boylan combined for Gavin Hoyte to poke the ball home.
Home goalkeeper Danny Potter, who was named as man-of-the-match by the home sponsors, then foiled Defty with a fine save, but the Linnets striker was offside.
Lynn's Francis, who looked at home on the big stage, left home defender Dan Gleeson for dead down the left, but his centre was well dealt with by Josh Coulson.
In the 34th minute, Courtney Pitt headed against the post from three yards out after Dean West's attempted header back to Scott Howie cannoned off the crossbar in a comedy of errors.
But less than a minute later Lynn's defence went missing again and it was 2-0 when Hoyte played in veteran striker Fortune-West, who looked suspiciously offside, before stabbing home his eighth goal of the campaign.
Yet another darting run from Francis resulted in Potter pulling off a fine one-handed stop five minutes before the interval.
Melton headed over at the start of the second period, Andrew Fisk fluffed his lines after a sublime Phil Mulryne pass and Potter denied Turner as Lynn started the second period well in command.
But perhaps the turning point of the whole contest came in the 64th minute when Jack Defty spurned the best chance of the match from eight yards out after turning home defender Mark Peters inside-out.
Such was Lynn’s dominance in the second half, angry U’s boss Quinn brought on the razor-sharp Rendell, whose introduction served as the final nail in the Lynn coffin.
Cambridge’s leading scorer netted the home side’s third with almost his first touch in the 66th minute when he shook off the attentions of Crane to head home Pitt’s centre from a tight angle.
The trio of Matt Nolan, Bloomfield and Defty were all thwarted by Potter as Lynn surged forward in search of a deserved consolation
As more gaps started to appear in the Linnets’ defence, a fourth goal arrived three minutes from time when a Pitt corner was flicked on by Robbie Willmott into the path of Rendell, who clinically volleyed home in a crowded penalty area.
Lynn were now out on their feet and the hosts completed the scoring three minutes into stoppage time when Boylan buried another cross from Pitt into the back of the net.
As Lynn’s players and coaching staff left the scene of their biggest defeat of the season, a chorus of “we’re going to win the league” could be heard from the 700-strong travelling fans, who were magnificent in their backing throughout the afternoon.
If Lynn can learn from their mistakes at the back and continue to carve open teams with their attacking flair, that could be a remote possibility come May.
Cambridge United: Potter, Brown (Willmott 75), Peters, Gleeson, Boylan, Pitt, Convery (Wolleaston 67), Carden, Hoyte, Fortune-West (Rendell 63), Coulson. Subs (not used): Morrison, Knights.
Goals: Hoyte (7), Fortune-West (36), Rendell (66, 87), Boylan (90).
Bookings: Brown, Gleeson, Peters.
Lynn: Howie, West, Chapman, Mulryne, Crane, Camm, Melton (Buhlemann 74), Fisk (Bloomfield 67), Defty, Turner (Nolan 62), Francis. Subs (not used): Lake, Murray.
Referee: D. Coote (Newark). Attendance 2,311.
Lynn News Man-of-the-Match: Joe Francis.