Allardyce: City are Jekyll and Hyde
West Ham will take confidence going in to their clash with Manchester City from both their memorable win at Tottenham and City's own faltering away form.
Sam Allardyce led the Hammers to a 3-0 victory at White Hart Lane before the international break after deploying a formation without a recognised striker.
City are the visitors to Upton Park on Saturday evening as West Ham look to build on their London derby success and Allardyce feels there is cause for optimism given the away form of Manuel Pellegrini's side.
"In terms of results they've been a little bit Jekyll and Hyde," Allardyce said.
"[They are] absolutely fantastic at home and unfortunately for them they've not won away from home yet - lost two and drawn one.
"We have to be encouraged by that. Last year we had a fantastic 0-0 against them."
City have lost at Cardiff and Aston Villa on their Barclays Premier League travels so far this season, with their only point on the road coming in a 0-0 draw at Stoke.
West Ham had won only once in the league until their success at Tottenham and Allardyce knows his squad need to put in another top-drawer performance if they are to take three points in front of their own fans for the first time since the opening day.
"Our top level players have to play at their top level as they did against Tottenham," he added.
"Anything less would make life difficult with the quality of their squad. If our players can exploit their weaknesses like we did against Tottenham I don't think we'll win 3-0 but I hope we do."
Allardyce revealed the decision not to play a striker at Spurs stemmed from the fact none of his fit forwards had found the back of the net with great regularity.
With Andy Carroll sidelined and Carlton Cole still searching for match fitness after signing a short-term deal, Allardyce still only has Mladen Petric, Ricardo Vaz Te and Modibo Maiga to choose from.
But Allardyce's main worry ahead of this weekend comes in defence where he will now be without James Collins, who suffered a hamstring injury whilst on international duty with Wales.
Although the 30-year-old has not featured in the previous two Premier League games, Allardyce believes his squad will be stretched to the limit with Winston Reid and James Tomkins his only fit centre-backs.
"I am concerned about the fact that we only run with three centre-halves," Allardyce said.
"So James being out is a particular problem for me because I have to run with only two central defenders now, James Tomkins and Winston Reid, for however long it takes James to get fit again, that is my big concern."
Meanwhile, Micah Richards is confident he is in manager Manuel Pellegrini's plans and has no intention of leaving City.
The full-back has played only twice this season, once in the Capital One Cup and once in the Champions League against Bayern Munich.
Injuries limited Richards to eight appearances last season and there had been speculation he may seek to leave the Etihad Stadium in search of a regular spot and to boost his England hopes.
The 25-year-old last played for his country in February 2012 and faces a race against time to force his way into Roy Hodgson's squad for the World Cup finals next summer.
Richards told BT Sport: "I did say at the start of the season I wanted to see the manager's plans and I'm in his plans, as he's said all along, so we'll see what the future holds, but I'm happy at Manchester City.
"I've been here since I was 14, it's a club I love.
"Before I got my injuries, I was number-one choice. It's only because I got injuries and Pablo Zabaleta has done so well, I find myself not playing as regular.
"I'm fully fit now and I'm ready to show everyone what I can do.
"It was a big decision for the manager to play me in the Bayern Munich game after only playing one game previously in the cup against Wigan so it shows massive confidence in me."
Meanwhile, defender Martin Demichelis is closing in on a first-team debut after pulling on a City shirt for the first time.
The Argentinian defender joined City at the start of September from Atletico Madrid but damaged knee ligaments in his first week of training.
Demichelis played 45 minutes in the elite development squad's 2-2 draw with Rochdale on Wednesday night.
With a return date for captain Vincent Kompany still uncertain, Demichelis' return to fitness has come at a good time, although Saturday's trip to West Ham may come too soon.
Demichelis, who played under Pellegrini at River Plate and Malaga, told www.mcfc.co.uk: "It was important to play and get the confidence back. My knee responded very well and I'm very happy after working very hard to get here.
"It was difficult at the beginning with the injury but that allowed me to meet everybody at the club and feel confident and comfortable with everybody so it's fantastic now and I'm looking forward to my debut."
Midfielder Jack Rodwell also played in the game, which City won on penalties, and has declared himself fit and available for West Ham.