Ulster are sweating on the fitness of Jordi Murphy, Jacob Stockdale and Stuart McCloskey for Saturday's Pro14 semi-final against Edinburgh at Murrayfield.
Flanker Murphy took a heavy hit 65 minutes into Ulster's defeat to Leinster last Saturday. The province confirmed on Tuesday that he sustained a concussion and is following return to play protocols.
Stockdale and McCloskey suffered contusions at the Aviva Stadium, with Ulster saying their fitness will be monitored during the week.
It's an unwelcome concern for head coach Dan McFarland who's already missing Will Addison, Sean Reidy, Robert Baloucoune, Luke Marshall and Iain Henderson.
Ulster had to cancel training in the run-up to the Leinster match after they identified a number of Covid-19 cases within their academy squad. The game got the go-ahead after neither squad returned a single positive result from the latest round of Covid-19 testing.
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