After limping past Ford Utd in the first round of the FA Cup, Scarborough would prove an uphill battle for Port Vale if their current form was anything to go by.
Before a chance was created, Boro keeper Leigh Walker risked his involvement in the tie, when Billy Paynter flicked on for Mark Boyd, but before he could get to it Walker raced out 30 yards to slide clear but in doing so could have been adjudged to have handled the ball.
Luckily for him, referee Stratton continued play.
On-form striker Steve McPhee probably had one of the only chances of the half when Michael Cummins played a throughball for him on 24 minutes, but he should have done better when his chip over Walker fell wide of the left post.
Walker did enough to prevent a Vale goal again after 38 minutes when he made an excellent stop when Boyd whipped in a cross from the right for defender Sam Collins, who had to watch his header being tipped over the crossbar.
Vale keeper Jonathan Brain was called into action for the first time in the 57th minute when Scarborough won a free-kick out at 35 yards that Wayne Gill swung in for Matt Redmile, but his header was pushed over the crossbar with a fantastic full-stretch save.
After having a 25-yard drive denied, Ashley Sestanovich made the Seadogs fans journey worth every mile when he burst through the Vale defence on 80 minutes and blasted a well-struck shot over the oncoming Brain from 15 yards to take the tie and ignite the away fans.
Joyous Scarborough manager Russell Slade said: "I am delighted with the result. We changed our way of play and came with a game plan.
"We were well rewarded with the goal and it's what we've been working on.
"There's hope that you'll always get a Premier league team in the next round, but this result will ensure wages for another month."