Striker Callum Wilson's knee injury is a "huge blow" to Bournemouth, says manager Eddie Howe.
Wilson, 23, was carried off on a stretcher 17 minutes into the Cherries' 2-1 defeat at Stoke on Saturday after injuring his right knee.
He had scored five goals in his first six Premier League matches, prompting talk of a first England call-up.
Howe said: "It doesn't look good. He's in a brace, he's on crutches and he's in a lot of pain."
Wilson was hurt in an innocuous-looking incident involving Stoke defender Philipp Wollscheid.
He attempted to play on after receiving treatment but went down 30 seconds after returning to the pitch.
Howe said: "He took a whack to the knee, thought he was OK to carry on but then collapsed."
Bournemouth are already without their two most expensive signings - full-back Tyrone Mings for the rest of the season and winger Max Gradel for six months - after the pair both suffered serious knee injuries in the same game, against Leicester last month.
Howe said: "It looks like it could be another serious knee injury. The players have had that three times this season, losing key players with bad injuries."