The caretaker boss hadn’t put a foot wrong after bailing the SFA out following the sacking of Gordon Strachan and was among the favourites for the job on a full time basis.
With no pressure on him, hours before the match with Holland, Regan announced to TalkSPORT that the former Cardiff boss would only be in charge for one match.
With Davie Moyes taking on the West Ham job the SFA are suddenly short of options with no sign of leadership from their Chief Executive.
Regan has presided over one disaster after another in seven years in charge but his latest howler has still surprised Provan.
Writing in The Sun he explained: “The SFA can’t wait until next summer for (Michael) O’Neill which makes his ruling out of Mackay before the Holland match all the more bizarre.
“Since handing Malky that game, Regan has had weeks to clarify Mackay’s position. He chose not to.
“Quizzed by the media on the possibility, Mackay made no attempt to rule himself out. Cue Regan’s radio appearance on the day of the game, when he hung Mackay out on a washing line.
“That was accompanied by the usual guff about Project Brave and the great job Malky is doing there. As if that position is remotely as important as the Scotland manager’s job.
“The idea that Mackay would be more useful reshaping the youth system is utter nonsense.
“He’s a time-served coach with experience of the highest level, not a Hampden babysitter.”
With more sensible options being ruled out it looks like the SFA may have to return to Alex McLeish to fill their problem vacancy.