Snainton led 2-1 at the interval after two goals from in-form striker Zac Hansen saw them battle back after going behind to Terry Day's early strike for Pier.
Johnny McGough's charges weren't to be denied though and were soon on level terms thanks to Christian Mattinson's superb solo effort.
The turnaround was completed when Day bagged his second to wrap up a 3-2 victory for Pier.
Brandon Catherall was the star man for victors Pier while Regan Hewitt was named as the man of the match for Snainton by boss Andy Holt.
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Edgehill Reserves cruised to a 4-0 win against Seamer Reserves.
Alec Coulson's men led 1-0 at half-time thanks to young right-back Max Wright's first goal for the club.
Their win was wrapped up thanks to second-half strikes from Jake Reeves, Jake Moore and Matty Rowley for a 4-0 victory.
Edgehill's win was tainted as young midfielder Liam Coulson had to be taken to Scarborough Hospital with a suspected broken leg.
Centre-back Connor Avison was Edgehill's man of the match after an assured display at the back, while Seamer's star man was defender Mitch Fisher.
Scalby Reserves beat Goalsports 3-0 at Pindar on Friday night.
Goalsports started brightly but fell behind when an attempted clearance struck Dan Virr in the face and the ball fell to George Wilson to tap Scalby ahead.
Their lead was doubled five minutes later when George Wilson turned provider for John Clifford to rifle high into the Goalsports net.
The win was wrapped-up thanks to Sam Foy's chipped effort in the second half.
Full-back Jack Rogers was man of the match for the Otters, with Liam Prescott also impressing.
Eastfield Athletic v Eastfield Town and FC Rosette's game against Cayton Athletic were both postponed due to a waterlogged pitches.