The Algeria international had made a bright start to the new campaign, scoring two goals and providing two assists in his first four Premier League matches.
Speaking to the press ahead of this weekend's game at the London Stadium, Moyes confirmed that Benrahma is his only injury concern following their 2-0 Europa League victory away against Dinamo Zagreb on Thursday.
"Said [Benrahma] got a knock on his knee when he came on [against Dinamo Zagreb] but apart from that I think we're fully available," the former Red Devils boss told the press on Saturday.
Moyes has also provided the Hammers fans with an update on left-back Arthur Masuaku, who made his first senior appearance of the season against Zagreb after recovering from knee surgery earlier this year.
"You can see that [Masuaku has] got a bit to go regarding his sharpness but we're trying to bring him back and get him as ready as soon as we can but is he completely ready? Probably not but he is on the way to getting ready."
One player West Ham will be without on Sunday is the suspended Michail Antonio, who was shown two yellow cards in the goalless draw away at Southampton last weekend.
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