Fabian Schar will learn this week if he requires an operation after sustaining a knee injury in the 3-2 win over Southampton.
The Swiss international was hurt after trying to follow up on a rebound after his free-kick had struck the wall.
Schar, who also suffered a shoulder injury at the end of last season, was carried off against the Saints on Saturday afternoon at St James' Park.
Whether Schar appears again in the Premier League again this season remains to be seen but the centre-back suggested he was hopeful he would be fit enough to play at the European Championships this summer.
Speaking to Blick in Switzerland, Schar said: "I don't yet know whether it needs an operation.
"But I'll do everything I can to be at the Euros. The Euros is realistic one way or another."
Schar has played 21 times this season for club and country and goes into the final year of his contract in June.
The fact Schar feels he could be OK for the Euros means there is an outside chance he could feature again for Newcastle this term.
Indeed, the season runs on until May 23 and the Euros is set to start in mid-June with Switzerland kicking off their first group game in Rome against Italy on June 16.
