It was a West Ham win over Wolves, of course, that set up the Fulham cup tie, but Chris Coleman's men found a trip to Molineux not so rewarding.
"They got beaten at the weekend which must have hurt them and they will be looking to prove a point," says Christian.
"It is going to be a difficult game, but we did really well in the first game - and it wasn't a fluke because we have been doing really well anyway.
"So it is up to us to keep it going, and do it in front of our home fans."
If West Ham do win, Matthew Etherington will be banned for the trip to Old Trafford following his expulsion at Norwich on Saturday after he got two yellow cards.
"That was a joke; the first one was not a booking anyway and the second? Oh my God," says Christian.
The second yellow card, for not placing the ball properly in the quadrant, left Christian scratching his head.
"It was ridiculous, and Mattie got pelted by about three things, I think, which was the reason he stopped in the first place," he explains.
"A couple of things came down, not that it bothered him, but I think that is why he thought the referee was coming over, to sort that out.
"It turns out that wasn't the case; it was a bit bemusing, but what can you do?
"I do not understand why he got his second yellow though apparently it was for taking the Mick out of the ref.
"But he was just asking him what he was actually wanting because it wasn't clear to him at all."
Christian believes West Ham have not had much luck with officials' decisions this campaign, and adds:
"Let's be honest, we get absolutely nothing - from the start of the season to now we have had nothing.
"Norwich have had about six or seven penalties this season and we have had one, is it?
"We just don't get anything and that is what we are up against, as well.
"Whenever West Ham go to play anywhere there is a good atmosphere and as big buzz and I think sometimes the referees get a wee bit over-excited as well by the occasion.
"At the end of the day they are only human.
"But if we keep plugging away, working as hard as we have been, we are confident the results will keep going."
Christian says he has every sympathy for Tomas Repka, whose back header was intercepted by Darren Huckerby for the Norwich equaliser.
"He did brilliant and he was sitting in there disappointed with the goal after the match; he had done so well and nobody is going to hold that against him," he insists.
"He will be fine and we have a great prize in store if we beat Fulham, the chance to go to Old Trafford."
The Hammers were beaten 6-0 at Old Trafford last year, but Christian says:
"It is a different side from last year and it will be interesting to see how it goes."
Christian's trip to Carrow Road at the weekend followed hot on the heels of his involvement with Scotland in their 4-0 defeat by Wales last week.
"I am an experienced professional and in many ways I enjoyed the experience the other night, playing in midfield for Scotland and captaining my country again," he says.
"I was running my heart out and that is all you can do when you go and play for your country.
"The team will take stick and the manager will take stick, but we never stop trying and give it everything when we play.
"But I didn't need to pick myself up at all to play for West Ham."