Curle, working in his capacity as a pundit for Sky Sports, felt Stephen Quinn should have been flagged offside in the build up to the goal. The midfielder was clearly in an offside position and made a move towards the ball before leaving it for Elliott Hewitt to cross, with Stephen McLaughlin converting.
That took Mansfield a giant step closer to Wembley and extended their overall lead in the tie to 3-1. They soaked up plenty of second-half pressure to hold on and seal a place in the League Two play-off final.
Analysing the incident at half-time, Curle told Sky: "I know what you say about ‘rules are rules’ but my understanding is that when you have made an attempt to go for the ball, the linesman has every right to put his flag up because a player in an offside position has made an attempt to get the ball.
"In those circumstances, I think I would have been speaking to the fourth official – in the right way – and asking for clarity on the rules.
"My interpretation was that if an offside player makes an obvious attempt to go for the ball, the linesman has every right to put his flag up.”
Fellow pundit Aaron McLean, the former Peterborough and Hull City striker, added: “Quinn is clearly in an offside position and he makes an attempt to go to the ball.
"Elliott Hewitt does brilliantly and says to Quinn to leave it. Eppiah doesn’t track the run and by the time he gets back McLaughlin tucks it away but I can understand (the frustration) because there is a clear offside in the first instance.”
The defeat ended Town’s hopes of promotion but Curle believes the club are well-placed to bounce back next season, adding: “It is going to hurt. What I would say about the football club is it's a very honest, well-structured club."
Meanwhile, co-commentator and ex-Aston Villa midfielder Lee Hendrie felt Mansfield could have had two players sent off in the second-half of Wednesday’s game. Kieran Wallace lunged in recklessly on Josh Eppiah shortly after half-time but only saw yellow whilst Quinn was not even booked despite appearing to slap Shaun McWilliams in the face off the ball.
On the first incident, Hendrie said: “I’ll tell you what, it’s a red card for me. You cannot lunge in that way. It’s reckless.” He also described Quinn as ‘very lucky' to stay on the pitch.
Wallace’s challenge forced Eppiah to come off with injury and Town boss Jon Brady gave his view after the game, saying: "It certainly curtailed Josh's night and it was a very heavy hit. A lot of people tell me that it should have been a red card.
"I'm not so sure but from my position, it did look a very physical challenge."