Assistant boss on LaticsAssistant Manager Kevin Keen expects Wigan to come out with all guns blazing tonight.
The Latics have surprised many with their results this season and currently sit inside the bottom three, nine points from safety.
But tonight's match is a game in hand for both clubs, who see it as an opportunity to climb up the table.
Keen told BBC Radio Berkshire, "We're expecting a tough game, they are in the scenario where they need to win games, we expect them to come and have real go because they have to win games to stay in the League.
"I was talking to Chris Gunter yesterday, we went to Wigan first game of the season and drew, he felt if we finished above Wigan we'd be in and around the play-offs.
"They've had a very tough season, change of manager, a lot going on. We've been looking at them on DVD over the last couple of games, I'm really surprised where they are with the squad they've got and the people playing for them.
"But like I say they will come and have a go."
Kevin also spoke about last night's FA Cup draw, taking the Royals up to Valley Parade to take on Bradford City.
Keen said, "I think it's a great draw, it gives both teams a realistic chance of making Wembley.
"The thing is, if you draw an Arsenal or Liverpool away, it's a great day but your percentage chance of getting a victory is probably not as great.
"So I think there's a realism that both teams have got an opportunity to get to Wembley, and for Reading that would be a fantastic achievement.
"I look at our form away from home in general, not just in the cup, the only one we've lost was at Fulham and probably our best performance of the year. Our away form has been good so in some respects it's decent to be away, but it'll be a tough game.
"It's a great draw for the media obviously because of Parky's association with the club and him being a club legend. It's a great draw and I'm really looking forward to it, but between now and then we've got five league games that are really important."