The back-row forward was hurt in the game against Northampton.
The 31-year-old went on as a half-time replacement for Billy Vunipola in a game that Saracens won 30-6.
In an injury update posted on the club’s official website, Saracens said that Wray would be “seeing a consultant this week after suffering a fracture in his skull last weekend against Northampton Saints”.
Wray has made more than 250 first-team appearances for the club.
Saracens’ latest Premiership victory – their eighth from 11 starts this season – kept them in second place, nine points behind unbeaten leaders Leicester.