Watford have made their 10th signing of the summer transfer window by bringing in defender Kevin Keben from French top flight side Toulouse.
The 20-year-old Cameroon Under-23 international has joined the early Championship pacesetters for an undisclosed fee on a four-year deal.
He will have to sit out his first month at Vicarage Road as he is still recovering from a knee injury.
"He's got a small knee issue," said Watford head coach Tom Cleverley. "So he won't be available straight away, but we expect him to be available towards the end of the month/start of October.