The former keeper said: “I felt for Rado because it’s a horrible moment.
“For any keeper, there’s no worse feeling when you lose such a goal, especially in such a big game when any mistake is highlighted 10 times over.
“Of course, Rado will be hurting.
“It was a bit similar to the kind of goal which won it for Dundee over 10 years ago at Dens.
“I was in goal that day and you do feel for your opposite number when it happens, but that’s football for you.
“I thought he would have easily taken Greg’s shot but it wasn’t to be and it gave Dundee such a lift.
“It’s the goalie’s union and you never like to see anyone being at fault like that.
“But Rado did have a great save towards the end which stopped it from being 4-1.”
Soutar added “It felt going into it that this was Dundee’s chance to put things right.
“I’m delighted they did because it’s been such a long wait for their supporters who’ve been put through the mill.
“They’ve suffered over the years and it’s remarkable to think it was over ten years since they experienced that kind of achievement.
“It was an amazing atmosphere inside Dens on Wednesday and you could see what it meant to the home fans at the final whistle.
“They were so up for it on the night and nobody could begrudge them their victory.
“Now I’m sure they can kick-on and if they can get top-six it would be a great achievement.”