Newcastle defenders Florian Lejeune and Paul Dummett will be out for a number of weeks after picking up injuries against Tottenham.
Dummett, 25, played only seven minutes before being forced off with a hamstring injury.
Summer signing Lejeune, 26, suffered ankle ligament damage in a clash with Harry Kane during the 2-0 defeat.
"Both players are expected to be out for weeks, rather than months," a club statement read.
Newcastle manager Rafael Benitez said after the match that Kane, who was booked for the foul on Lejeune, should have been sent off.
The Magpies, winners of the Championship last season, face Huddersfield, who were promoted via the play-offs, on Sunday.