On a glorious afternoon the two sides produced a terrific game, with chances at both ends, but the extra experience of Pier's senior players just gave them the edge, writes Steve Adamson.
The first half was evenly contested, Martin Cooper flicked a shot narrowly wide for Pier, and then drove a free kick into the Seamer wall, while a low ball across the goalmouth from Benny Davis was scrambled clear, Jayden Rodgerson fired a stinging shot at keeper Connor Myersough, and Neil Thomas headed inches over.
Seamer probably created the better chances, with Kris Tate volleying just over, Gary Lawton shot inches past the far post, and a surging run from Tom Greenwood ended with his shot being blocked by Jake Adams.
A Tate corner was headed goalwards by Lawton, but blocked on the goal-line by Sam Garnett, then just before the interval, Pier keeper Scott Wardman pulled off a superb save, diving to tip away a shot from Lawton.
West Pier were the better side for much of the second half, but Seamer defended resolutely, and were dangerous on the break.
A Garnett cross was headed over by Cooper, Will Jenkinson played a precise through-ball to Neil Thomas, who shot wide, then Cooper also fired wide.
In Seamer attacks, Tate volleyed high over the bar, Oli Parker was foiled by a great tackle from Mikey Pickering, and a Tate free-kick was headed narrowly wide by Tommy Adams.
Pier's pressure intensified in the final quarter of the game.
Myerscough saved a Cooper shot, Ross Pluu burst past two defenders before his shot was tipped over by the keeper, then an in-swinging corner from Cooper was cleared off the line by Chris Stubbings.
A corner from Cooper was headed over by Jenkinson, before the breakthrough finally arrived in the 88th minute, when substitute Paul Provins, who had only been on the pitch five minutes, rose to head home a Cooper corner at the far post to settle an excellent, action-packed game.
Tenacious midfielder Sam Garnett was outstanding for Pier, and other players to impress were Martin Cooper, Ross Pluu and young Jayden Rodgerson for Pier, and Gary Lawton, Tom Greenwood and Tommy Adams for Seamer Sports.
SEAMER SPORTS: Myerscough, Adams, Lowry, Bradbury, Staniforth, Tate, Appleby, Adams, Greenwood, Parker, Lawton subs- Metcalfe, Walton, Stubbings, Sheader, Messruther
WEST PIER RES: Wardman, Rodgerson, Pluu, Adams, Pickering, Garnett, McNiven, Jenkinson, Thomas, Davis, Cooper subs- Wood, A.McNaughton, Hartnett, Provins, M.McNaughton
REFEREE: John Chalk
MAN OF MATCH: Sam Garnett (West Pier Res)