Southampton manager Claude Puel has revealed striker Charlie Austin is likely to need surgery on a dislocated shoulder and could be out for between three to four months.
Austin was substituted during the first half of Saints' 1-1 draw with Hapoel Be'er Sheva in the Europa League on Thursday with what Puel said was a dislocated shoulder.
Southampton edged past Middlesbrough 1-0 without Austin on Sunday and after the match, Puel said the striker is likely to need an operation.
"Normally he needs surgery and will be perhaps between three months and four months (out)," Puel said.
"It's a good estimation for the time after the surgery. Is it dislocated? Yes I think. Will it need surgery? Yes, normally yes."
Austin's extended absence comes as a major blow for Southampton given he has scored nine goals already this season and six of their 14 in the Premier League.
"It is important all the players take (responsibility) without Charlie. All the players can take his place," Puel said.
"Of course it is difficult to play without Charlie because he scores a lot of goals for us. It is important now to look forward with other players."
One source of attacking inspiration could be Sofiane Boufal, whose stunning strike from 25 yards was enough to seal a hard-fought victory over Middlesbrough.
Southampton signed Boufal for a club-record deal worth £21million in the summer but he has taken time to settle after arriving injured from Lille.
The 23-year-old is an unpredictable talent and he showed all sides of his game at St Mary's, with a frustrating first half coming before a match-winning contribution in the second.
"Sofiane is a talent but also it is important to work with a good attitude," Puel said.
"For example in the first half we saw a lot of dribbles without a good thing, he lost a lot of balls. It was not a good Sofiane.
"It was important he came back in the second half and found a good solution when he plays one or two touches and keeps his spontaneity.
"He is a good player with talent. It's important he makes progress and after that he can be the difference every time because he has fantastic quality."
While Southampton climb to 10th in the table, Middlesbrough remain 16th with only one victory in their past five games.
Boro struggled for chances again and Aitor Karanka's side are now the least prolific in the division, having scored only 13 goals in their 15 league matches.
Alvaro Negredo was out with a hamstring injury, which meant Jordan Rhodes was handed only his second start of the season.
"It was difficult, he had his chance," Karanka said.
"He is a player who has played today. I knew one day he would have his chance and he is there."