Vale headed down the coats with just 11 fit players plus two drafted in from their under-21s.
But they went straight into the attack against a young but very good Largs team and were unfortunate not to score two minutes in when Del McNab’s effort went narrowly past.
Three minutes later Scott Davidson and Liam McGonigle linked up and the cross to the far post was just missed by David Leadbetter, sliding in.
Largs had a great chance on the half-hour mark when George Sewell’s cross found Scott Adam unmarked, but his rushed effort went well over.
But Vale were doing most of the pressing and Peter Bradley had two efforts cleared along, with McNab, in a stramash following a McGonigle corner.
However they were again nearly caught out as, from a long clearance upfield, Paul Harkins found Adam who again blasted over from close in.
Just on half-time Matt Niven looked to given Vale the lead with a great header from a McGonigle corner, but his netbound effort was cleared off the line.
After the break Davidson suffered a similar fate with a shot after McNab stepped over a ball played into the Largs box.
Largs were always dangerous going forward and Sewell tested Jamie Donnelly with a good effort but the Vale keeper made the save.
The best move of the game then came when McGonigle linked up with McNab before bringing out a good save from Largs keeper Ross Lundy, who saved again from Gary McGrath’s header from the resultant corner.
With ten minutes to go Vale were reduced to 10 men after McGrath was adjudged to have stopped a Largs player bursting through the middle.
The last chance fell to the visitors when young Luke Traynor from 21s found Johnstone who then played the ball wide to Leadbetter but he blasted wide of target and the game finished goalless.