But he fears Sam Allardyce will keep faith with Dutchman Andre Ooijer in the Premier League as Blackburn are in the thick of a relegation scrap.
Simpson said: "I had a good run at the start of the season and I want to play in the Premier League.
"But the guy who is in my position has won so many caps for his country. He has been around the game for years.
"He has a lot of experience and with the situation Blackburn are in at the moment the manager is going with him.
"But I will continue to work hard on the training ground and if Andre gets banned or injured I have got to be ready to step in."
Simpson's Wembley dream appeared to be over, only for Christopher Samba to force a replay in stoppage time.
Samba was left with mixed emotions. Not only did he pick up a yellow card which rules him out of the game against Manchester United on Saturday, he got in the way of Michael Doyle's effort, which gave the Championship side the lead with 15 minutes remaining.
It seemed as though the visitors were heading for the quarter-finals but Samba took advantage when stand-in goalkeeper Andy Marshall fumbled substitute Keith Treacy's effort.
Marshall was left distraught after replacing Keiren Westwood, who was taken ill during the warm-up.
But this was fiesty performance by Coventry after they went a goal behind in the second minute.
Roque Santa Cruz gave Blackburn a perfect start by rattling a superb shot into the corner following a flick-on from Samba.
Coventry, however, raised their game and Aron Gunnarsson pulled them level on the hour with his first goal for the club - a spectacular strike from 20 yards.
Then Doyle put his side within touching distance of the last eight only for Samba to force a second match between the sides.
Coventry manager Chris Coleman was delighted with the contribution of his goalscorers.
He said: "Aron's all-round performance was very mature for a 19-year-old.
"It was a great goal to cap his performance off. I am glad I stuck him in midfield.
"As for Michael that is three goals in three games and he is making good driving runs into the box."
Coventry will host the replay a week tomorrow but Coleman is refusing to take anything for granted.
He added: "It is going to be equally as hard. Sam Allardyce has paid us a compliment by fieldng a lot of players with Premier League experience and it will be a tight game."
FA Cup 08/09 Win Outright: Blackburn 25/1