Offiah, one of Wigan's ex-rugby union stars, has been out of action for more than a month after breaking a small bone in his back during his side's Super League defeat at St Helens on Good Friday.
But the 29-year-old try-scoring sensation should be fit to face rugby union's double winners Bath at Maine Road in the first leg which will be played under League rules.
Offiah is eager to play against Bath, saying: "It's another big stage and a lot of people will be watching, not only from rugby league but also from rugby union as well. There will be a lot of people interested in the outcome of both games."
The Wigan side will also include ex-All Black Va'aiga Tuigamala and former Welsh rugby union international forward Scott Quinnell, who has been strongly linked recently with a permanent return to union with Courage League Second Division Richmond, and an announcement could be made within the next few days.
Shaun Edwards, the Wigan captain, is another relishing the Bath games, and he said: "I feel privileged just to be involved in this. There has been a lot of bigotry in rugby union against rugby league in the past 100 years, whether it's a class thing I don't know.
"Certainly, these games can prove a lot of things. We've got to worry about how good we are on the night, not how good Bath are. If we are at our best, the rest will look after itself. If we don't do well on Wednesday and Bath happen to beat us, we'd never hear the last of it.
Wigan said yesterday that 20,000 tickets had already been sold for tomorrow's game and officials are hoping there could yet be a 32,000 sell-out at Maine Road. All 82 executive boxes have been sold, while all 120 have already gone for the rugby union return at Twickenham on 25 May.
It has been reported that the two games could bring in revenue of pounds 2m. Whatever Wigan do make will be particularly welcome after their failure to get to Wembley this year for the first time since 1987.
Wigan (probable): Radlinski; Robinson, Tuigamala, Connolly, Offiah; Paul, Edwards; Cowie, Hall, O'Connor, Quinnell, Cassidy, Farrell. Substitutes (from): Skerrett, Haughton, Smyth, Murdock, Johnson.Reuse content