Queens Park Rangers forward Eduardo Vargas will miss the rest of the season after suffering knee ligament damage during Saturday's 4-1 win at West Bromwich Albion.
The Chilean, who scored as Chris Ramsey's side gave themselves a huge boost in their battle for Premier League survival, had to be substituted before the break.
A statement on the official QPR website said: "Scans have revealed Vargas sustained a grade two medial collateral ligament injury, which is likely to keep him sidelined for between 10-12 weeks."
QPR coach Ramsey, speaking at a news conference on Monday as he prepared his side for a crucial trip to fellow strugglers Aston Villa on Tuesday, said the Londoners needed to build on Saturday's performance.
"We want to put pressure on the teams around us," he explained. "Everybody seems to be responding to what others are doing. The pressure is equal."
Rangers would escape from the relegation zone and put Villa in it if they can take all three points, and the coach said: "Villa are close to us, and they are going to want three points to climb further up above the line.
"We are hoping that we can be as clinical as we were on Saturday."