Marshall's third and final goal was a stunning effort, with Pier player-boss Johnny McGough hitting a brace and goals from Taylor Jordan and Dave Wedge wrapping up the scoring.
Mikey Anderson was Pier's man of the match.
Dan Thomas netted for Athletic.
Ayton sealed a 3-1 win at Newlands Reserves.
Player-boss Sean Pinder scored a penalty for his side, whose other goals came from Mark McNulty and Will Jones, but the manager couldn't name a man of the match after a poor performance.
Fin McGregor was Newlands' goalscorer, while Ellis Sellars was Park's man of the match.
Seamer Reserves and FC Rosette shared the spoils after a 2-2 draw.
Graeme Reid volleyed Seamer into the lead, but Finley Davison-Ward equalised for Rosette after the break.
Ollie Parker's solo effort handed Seamer the lead again, but Rosette battled back through Tom MacDonald to seal a draw.
Reid was Seamer's man of the match, while Sam Loy shone for Rosette.
Goldsborough United battled to a 2-1 win at Eastfield Town.
Town led 1-0 at half-time, but Ben Watson and Jonathan Morrison scored second-half goals to seal the win for United.
With one minute to go, Goldsborough defender Richard Davies stopped a certain goal for Eastfield with a superb challenge.
Despite a poor performance, Goldsborough sealed the maximum points against the 10 men of Town.
Cayton Athletic and Fishburn Park Reserves shared the spoils after a 2-2 draw.
Park led 2-0 thanks to goals from their man of the match Marc Usher and Rob Ingham.
Athletic clawed their way back into the game though, Michael Hernandez scoring from a Freddie Schmuck corner, before Macauley Riley was taken out in the box and Schmuck took the penalty, seeing his spot-kick saved by Carl Oliver but reacting quickest to tap in the rebound.
Cayton player-boss Macauley Youngson couldn't name a man of the match, but was impressed with Harry Cooper, who played well coming off the bench.
Cayton Athletic 2-2 Fishburn Park Reserves, Eastfield Athletic 1-7 West Pier Reserves, Eastfield Town 1-2 Goldsborough United, Newlands Reserves 1-3 Ayton, Seamer Reserves 2-2 FC Rosette