Crystal Palace midfielder Adlene Guedioura will miss at least six weeks of Premier League action with a punctured lung and two broken ribs.
The 27-year-old was carried off at the Hawthorns after colliding with West Bromwich Albion goalkeeper Boaz Myhill during Palace's 2-0 defeat on Saturday.
Interim boss Keith Millen said: "It doesn't look good. The trouble with cracked ribs is that you can't exercise and you can't get your heart and lungs going."
He added: "Some injuries, you can keep your cardiovascular fitness up but with this injury you can't do anything."
Guedioura will miss the games against Everton, Hull City, Norwich City, West Ham and Cardiff City, but could be available again for the trip to Chelsea on December 14.
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