Ten-man Chesterfield ended a great week with a 3-0 loss at home to Scunthorpe United, the match level until the second half dismissal.
Goal-less and even at the break the game's pivotal moment occurred when Dan Jones was issued with a red card for a tackle that also resulted in a Scunthorpe penalty.
Paddy Madden slotted home the spot-kick and scored another after former Chesterfield striker Gary McSheffrey had doubled the away advantage with a brilliant volley.
After the game, manager Dean Saunders had no doubts about the game's turning point: "It was the red card and the penalty that decided the game, the game was quite even in the first half.
"We were playing really well at the time, ten minutes into the second half. We got a freekick, it went straight into the 'keeper's arms, he punted it up the pitch, there was a mis-kicked clearance, a through ball and Dan Jones gave a penalty away.
"That meant we were up against it, and then their second was a goal of the season contender - there's nothing you can do about that volley from McSheffrey - then the third goal took a deflection."
Moments before Jones's red card Scunthorpe had come close to losing a player themselves, and Saunders felt hard done by.
"Scott Wiseman got booked and then 20 seconds later he lunged in with a tackle on Sam Morsy," he said. "The referee gave a freekick, didn't book him to send him off and I don't know why he hasn't.
"I thought we played well when we went down to ten men, unfortunately the referee's not sent Wiseman off - then they took him off minutes off, which was a clear indication of what they thought would happen next.
"Those decisions decide games, and there's not much more to be said about the game."