West Ham defender struggled in win.
West Ham United won against Crystal Palace on Saturday.
The West Ham United pair are battling it out for the left-back starting spot under Manuel Pellegrini.
Masuaku lasted the entire 90 minutes as West Ham beat Cardiff.
The Hammers left-back will have a late fitness test ahead of Tuesday's Premier League game against Cardiff, with Arthur Masuaku potentially deputising.
West Ham United may be in the market for a new left back.
West Ham United's Arthur Masuaku had an afternoon to forget.
West Ham United were beaten by Manchester City today.
West Ham United could be in the market for a left back in January.
West Ham United left-back Arthur Masuaku has played eight times for Manuel Pellegrini's side so far this season.