The Latics have lost their last two matches - to Burnley and Blackpool - and are aiming to respond with a victory at Birmingham which would confirm their place in the top six with one game to go.
James Perch
James Perch: "We've got to try and bury Birmingham and secure our own play-off place.
"Birmingham lost at the weekend (at home to Leeds) and they'll be low on confidence but they'll have fight and spirit like Blackpool and we've got to conquer that and be ruthless."
The Blues have won just two home games all season and not since October 1 against Millwall.
Perch, who hopes lessons have been learned from the Blackpool match, added: "Their home form isn't great, it's 90 minutes and stats etc. don't really matter on the night; it's about what we can do.
"Not scoring the first goal proved to be vital, especially in a game where Blackpool were scrapping for their lives.
"I think if we (had) got the first goal they'd have been dead and buried - it just didn't happen for us on the day.
"Our focus is on Tuesday, if we get the three points there we secure the play-off place.
"We always knew we'd need the three points to secure that spot so Blackpool is one game chalked off and we have to go again against Birmingham."
If Birmingham lose and Charlton beat Watford, the Blues, Doncaster and Millwall will be scrapping on the final day to avoid joining Yeovil and Barnsley in League One.
Under pressure Birmingham manager Lee Clark made a rallying call to his players to fight for their lives after another heavy Championship home defeat.
Lee Clark
After watching his side ominously drop into the relegation area for the first time this season with a 3-1 loss to Leeds, Clark defiantly said: "I am extremely confident that I can rally the players and lift them to get the necessary points.
"It is hurting me and my family. It is affecting the enjoyment of living in a fantastic part of the world.
"It is not great, so I am prepared to do everything to keep us in the league. I know that I can do it.
"I believe that I have the backing of the players. A bit of nervous tension has crept in and we need to find a way of eradicating this in the last two games.
"Our poor home form is reality. I cannot affect the past but I can the future so why not go out with bang in our last home game against Wigan by winning?
"That would set us up for the last match of the season to give us an opportunity to stay in the league."