Northern Ireland have been dealt another potential blow ahead of their their first two World Cup qualifiers next week after Paddy McNair pulled up in Middlesborough's win over Preston North End on Tuesday night.
The defender was forced off in the 58th minute of the 2-0 victory with what manager Neil Warnock described as a knee problem, and was replaced by international team-mate George Saville.
"It's a strange one, it's the front of his knee cap," Warnock said. "He knew straight away that he had to come off. We will have more (on Wednesday) about that.
"If he can’t play he won’t be going (on international duty) but I won’t say that until we know the damage."
McNair absence's would be a huge hit for manager Ian Baraclough, who would have been relying on the 25-year-old being a key member of his squad for the games against Italy and Bulgaria.
Northern Ireland are due to travel to Parma for their opening game on March 25 before welcoming Bulgaria to Windsor Park on March 31, with a friendly against the USA in between on March 28.
After a disappointing Nations League campaign shortly after taking over from Michael O'Neill as the international boss, Baraclough would have hoping for a positive start to the qualifying campaign to gain some momentum.
However, not only is McNair potentially absent for next week's games, the manager could also be without striker Liam Boyce, whose wife is about to give birth, but he is set to give Accrington Stanley striker Dion Charles his first call-up to the squad.