Hickey injured his left cheek bone in the match against Leicester (Getty)

The Exiles are without Paul Hodgson, who is on the bench for England's match against with France in Paris.

With Shane Geraghty, Eoghan Hickey and Peter Richards all injured Irish are desperately short of half-back cover.

But Smith told BBC Radio Berkshire: "It's an ambush waiting to happen if we don't go there fully loaded."

Interview: London Irish scrum-half Warren Fury

Interview: London Irish director of rugby Brian Smith

"I don't think we've ever been to Worcester when it hasn't been extremely physical. They're going to throw everything at us and we're going down to throw a bit back.

Good teams back up great performances with another one. We can't let ourselves down. Brian Smith

"We're confident if we can raise the tempo of the game, we'll be good enough over 80 minutes. But we have to put them to bed physically first."

Warren Fury will start at scrum-half. Smith admitted they are stretched but he has faith in the Welshman.

"We're a little bit light - to say the least - at nine and ten. With Pete Richards being out and Paul Hodgson being called up we only have one senior nine and Catty is the only senior ten.

"It's really testing the resources of the club. It's times like this you wish you were Leicester with 50-odd senior contracted players. But an opportunity has opened up now for Warren Fury and he's a very good player."

Irish beat Warriors 23-16 in the fog in December (Getty)

Having beaten Leicester Tigers 22-13 last Sunday, Smith said it is vital the team follow up that result with another win.

"Good teams back up great performances with another one. Last weekend was a great result for the club from all 22 players. But this week, we have to win again. We can't let ourselves down."

Irish beat Worcester 23-16 in Reading in December. Although the Warriors have just one win this season, Smith thinks they are better than their results suggest.

"They seem to have been desperately unlucky a lot of the time. There's enough quality in that squad for them to be competitive. "