Jim Goodwin expressed his surprise at Gary Holt's resignation as Livingston boss in the wake of Saturday's loss to St Mirren.
Holt had stated he would consider his future following the 1-0 home Premiership defeat to the Buddies, which extended their winless run to five league games and left them in 10th place.
The West Lothian club confirmed on Thursday morning they had accepted Holt's resignation.
Saints boss Goodwin said: "I found out after training this morning.
"Of course I am surprised. It's not very often you hear of managers stepping down these days.
"I am not too sure of what has gone on behind the scenes. Obviously they haven't had as good a start as they had last year, maybe that has had a part to play in it, but obviously you are always disappointed when good people find themselves out of work.
"I haven't had too many dealings with Gary on a personal level, but in crossing paths he has always been a decent guy.
"I don't know the ins and outs of it, but whatever the reasons are I wish Gary all the best."
Goodwin took no satisfaction from the retrospective action taken on Jason Holt for the tackle on Brandon Mason which leaves the Saints player "touch and go" for the Betfred Cup tie against Aberdeen in Paisley at the weekend.
The Livingston midfielder's challenge on Mason went unpunished at the time but the West Lothian club accepted a notice of complaint from the Scottish Football Association's compliance officer and Holt will serve a two-game ban.
Asked if he was pleased to see the retrospective action taken, the former St Mirren captain said: "First and foremost, Brandon's ankle took a real heavy challenge.
"We got him scanned and the results of the scan weren't terrible but they weren't particularly great either.
"This weekend may come too soon, hopefully we will have him available for the next league game against Aberdeen.
"With regards being happy with retrospective punishment, it is not something we called for.
"The incident has been highlighted on numerous media platforms and obviously the SFA chose to look at it.
"I don't think Jason Holt went in with any real malice or meaning to hurt Brandon but it was a heavy challenge.
"Maybe 10 or 15 years ago it would have been one I would have been proud of myself, but unfortunately in the modern day game you just don't get away with that and he has suffered the consequences."