London Irish boss Brian Smith expects "a thorough examination" of his team when Aviva Premiership champions Harlequins arrive at the Madejski Stadium on Sunday.
Although Quins lost their last two league games against Saracens and Exeter, they bounced back with successive Heineken Cup victories over Biarritz and Connacht.
"It will be a tough afternoon," Smith said. "We can expect a thorough examination in all departments as Harlequins have a strong pack and some extremely dangerous back-line players. While we have a healthy respect for our opponents, we have faith in each other and the belief that we can beat any team in this league."
Irish have collected just nine points from their opening six Premiership games - only Sale Sharks' record is worse - but a 37-19 drubbing of league leaders Northampton three weeks ago suggested that 11th could be a false position.
Skipper Declan Danaher will make his 250th appearance for the Exiles, and Smith added: "It is a great milestone for one of London Irish's finest warriors.
"It is an incredible feat of endurance and courage."
Quins are again without injured fly-half Nick Evans, although he is on course to return against Gloucester next Saturday, while centre Jordan Turner-Hall rests a knee complaint before linking up with the England squad on Sunday.