Police made 29 arrests after they were pelted with bottles in city-centre disorder which forced the closure of the Metro for a short period.
And Newcastle have promised to ban for life any supporter found guilty of taking part in the disturbances.
A club statement read: "We were embarrassed and appalled by the behaviour of a minority of so-called fans who last night were involved in disturbances and disorder in Newcastle city centre after the match.
"Newcastle United have been working with Northumbria Police, and will continue to do so, in order to identify all of the individuals concerned.
"The club will take the strongest possible action against those involved in the disturbances and will impose immediate lifetime bans on all those found guilty.
"These deplorable individuals have no place at Newcastle United and bring shame on the club and the vast majority of its proper, law-abiding, fans."