However, the resulting free kick was easily claimed by Sam Slocombe.
Midway through the first half, Wycombe came close again with a header that flew over Slocombe's crossbar, but just a minute later, Scunthorpe had two gilt-edged chances to open the scoring - a David Mirfin header being cleared off the line before Dave Syers's follow-up effort was saved.
Towards the end of the half, Syers had a header of his own cleared off the line, before Max Kretzschmar blasted the ball over from six yards out.
Five minutes after the restart, Scunthorpe came close through Niall Canavan but his header soared over the bar.
Moments later, Eddie Nolan also got his head onto the ball following a corner, but again it was wide of the Wycombe goal.
Midway through the second half, the Iron threatened with some dangerous efforts, Gary McSheffrey's cross rattling the crossbar and successive chances from Winnall and Matthew Sparrow bringing the best out of Matt Ingram.
The Iron were forced to play the final 15 minutes of the game with 10 men after McSheffrey hobbled off the pitch, the home side having already made all three substitutions.
Despite the numerical deficit, the hosts were on top in terms of possession and chances, but couldn't break the deadlock.