The decision led to the Saints' first goal and Seb says: "I jumped and the ref said I made a foul but the the ref said at half time he made a mistake. He is not an English ref I know and it is very disappointing.
"There must be an improvement on Saturday. It was very disappointing on Wednesday because in the first 35 minutes it looked easy to win.
"We have to win on Saturday. It is very difficult to explain because Southampton are not a fantastic team - but everybody will forget that game if we beat Blackburn," he adds.
"We have to do it on Saturday and I'm glad the game is coming up now rather than a week later.
"We have to win and I'm very disappointed for the 3,000 fans that came on Wednesday.
"If we play with another mentality we will win. With more quality and more heart it is possible to win this game.
"Paolo didn't see too much of the ball and I didn't - but after the first 35 minutes it looked easy to win the game."
As for thoughts of revenge for the 7-1 defeat earlier in the season, he says: "It was the first time I have lost 7-1 and I want to prove to the fans it was a one-off mistake."