A three-goal flurry midway through the second half helped Cedars Park create a six-point cushion over fourth-placed Harpers at the top of the Kingsley Healthcare Suffolk & Ipswich League Division Five table this afternoon.
It leaves the Lions four points adrift of leaders Westerfield United A with seven games each to play.
The visitors took to the field with continental numbering, no 3 or 10 shirts, 9 in the centre of defence, 4 at centre forward and 14 and 16 on the field with substitutes wearing 19 and 20.
But it was the home defence which was left at sixes and sevens after 15 minutes when a free-kick was headed back across goal and Jason May beat Craig Dootson to the ball to score.
It took the Lions only two minutes to pull level and they never looked back, creating a wealth of chances to win the game comfortably.
The equaliser was set up by fast-raiding winger Tom Coe, who crossed the ball for Danny Moore to fire home from the corner of the penalty area.
Cedars Park had a let off seven minutes later when they allowed a forward a free run at goal but he screwed his shot horrendously wide.
Tommy Lankester then had a close range effort blocked when Harpers goalkeeper Chris Webber cleared poorly. The rebound fell for Moore but Webber redeemed himself with a good save.
Cedars Park went ahead six minutes before half-time when a scramble from a corner saw Craig Tostevin stab in a loose ball.
Felixstowe almost equalised in the 44th minute when Ross Young chipped the ball past Dootson but Simon Anderson was alert to the danger and put in a superbly-timed covering tackle in his own six-yard box.
Tostevin did not get enough power on a 49th-minute shot to beat Webber and the Felixstowe team almost made it costly but Lewis Clarke could only blaze wide when he exploited space at the back.
The Lions netted their crucial third goal after 70 minutes when Lankester burst clear and outpaced the defence before tucking the ball past Webber for his 14th league goal of the season to go top of the charts with Stephen Holland.
That was short-lived though, with Holland's 18-yard shot slipping through Webber's fingers to make it 4-1 six minutes later.
And within 60 seconds it was 5-1, this time visiting captain Graeme Conner getting in the scoresheet when he diverted Lankester's pass past his own keeper.
Dootson pulled off a superb one-on-one save to deny May in the last minute.
Cedars Park: Dootson, Edwards, Tostevin, Thompson (Hall 79), Jacobs, Anderson, Coe, Henke, Lankester, Holland, Moore. Substitutes (not used): Kennedy, Muskett.
Booking: Hanke (foul, 16).
Goals: Moore (17), Tostevin (39), Lankester (70), Holland (76), Conner og (77).
Felixstowe Harpers: Webber, Farrow, Conner, Gordon, Atkins (Jones 54), Gormer (Mahabir 75), Smith, Clarke, Young (Mitchell 87), May, Jones.
Bookings: Conner (foul, 66), Smith (foul, 90+3).
Goal: May (15).