Manchester - Premier League leaders Manchester City hope Sergio Aguero's early return from injury can spark an immediate response after their latest Champions League meltdown.
Manuel Pellegrini's side were buoyant after winning their opening five Premier League matches, and so it was all the more surprising that on Tuesday they lost 2-1 at home to a Juventus side who have started the Serie A season poorly.
The task now for City is to pick up their domestic momentum again, by claiming a 12th successive Premier League victory.
However, standing in their way are a West Ham side who have collected away wins over Arsenal and Liverpool already this season.
With that kind of record on their travels, Slaven Bilic's side are not to be taken lightly.
Amid their midweek European gloom, one piece of good news for City has been the quick recovery of Sergio Aguero from a knee injury.
The Argentina striker, forced off during the first half of last Saturday's 1-0 win at Crystal Palace, was initially ruled out of the Juventus game, only to appear for the last seven minutes as a substitute.
"It was a risk to use him," Pellegrini said. "I tried not to because if he got a kick in the same place, it could take him more days to recover.
"Fortunately he did not have any problems and I hope he will be fit for Saturday."
In defence, City will check on the fitness of captain Vincent Kompany, who has been instrumental in the clean sheets they have kept in each of their five league games so far.
Kompany came off with a calf injury 15 minutes from the end of the defeat against Juventus, although he suggested that was nothing to worry about.
"It's not serious," he said. "I know my body."