Wycombe were left frustrated by Port Vale goalkeeper Ryan Boot who made several good saves in a 0-0 draw at Adams Park.The Valiants' winless run was extended to 14 games but this will feel like a point gained against a side pushing hard for promotion.Boot was forced into action early on when he tipped over a header by Adebayo Akinfenwa from a Joe Jacobson corner that bounced awkwardly.Boot then just did enough to keep out another header, this time by Sido Jombati, from another Jacobson set-piece just before the break.Tyrone Barnett nearly broke through for the Valiants after 63 minutes when his low shot from 25 yards was superbly kept out by Scott Brown at full stretch.Wycombe substitute Scott Kashket then had a long-range effort comfortably saved by Boot, who also had to be alert in beating away a Craig Mackail-Smith shot as Vale held out for a point.