Newcastle United captain Bruno Guimaraes is expected to be out for a couple of months after sustaining a hamstring injury.
The Brazilian hobbled off in the closing stages of Tuesday night's 2-1 win against Tottenham Hotspur in just his second appearance since recovering from a separate ankle issue.
Head coach Eddie Howe said at the time Guimaraes was "a little bit worried because he has never had a problem with his hamstrings before".
Guimaraes is now set for an extended spell on the sidelines in a huge blow for Newcastle.
Newcastle have, obviously, lost games Guimaraes has played in before, including a 3-2 loss against Brentford last week.
However, Howe's side have failed to win any of the 10 Premier League matches in which the influential Guimaraes did not feature since his debut in February 2022.
Newcastle, by contrast, have a 53.1 win percentage with Guimaraes in the side in the top flight.
They have also picked up significantly more points per game (1.8), scored more goals per match (1.9) and conceded fewer goals on average (1.2).
But Newcastle are going to have to find a way to win without their talisman as they embark on a crunch run of games, starting with Saturday's FA Cup fourth-round tie against Aston Villa.
Sandro Tonali, Joe Willock and Jacob Ramsey are Newcastle's only three senior central midfielders available for the trip to Villa Park.
But Newcastle expect Joelinton to return from a groin injury imminently while the club hope Lewis Miley will not be sidelined for too long with a dead leg.