Yet it was Walsall who will have been by far the happier side with the stalemate at Oakwell.
Saddlers boss Paul Merson had brought in three players on loan in the lead up to the tie and as a result saw his side produce a much improved performance.
Stand in striker Kevin James, on loan from Nottingham Forest, was a threat to the Barnsley defence while fellow frontman, Manchester United's Mads Timm, provided the craft and guile.
And Michael Leary, brought in to strengthen the midfield, popped up in both boxes to good effect.
Indeed, it was Walsalll who were the better side in the first half yet they struggled to create clear-cut chances.
The closest they came was a far post header from James after eight minutes that was turned behind by home keeper Nick Colgan.
Walsall keeper Andy Oakes produced good saves from Paul Reid abd Robbie Williams as a lethargic Barnsley tried to find some rhythm.
Barnsley manager Andy Ritchie delivered a few choice words during the break and it was no surprise when his side raised the tempo in the second half.
Chris Shuker and Stephen McPhail both went close but it was Walsall who grabbed a 75th minute lead against the run of play.
A slick break lead to James lashing a low right-foot shot past Colgan.
Just three minutes later, Hayes pounced on an error by Oakes to deliver the equaliser for his 10th goal of the season.