Djenepo has not played for Saints since scoring in a 1-0 win at Sheffield United in the Premier League last month and Hasenhuettl said he hoped the 21-year-old close-season recruit would return to training after the international break.
"It's very difficult to say when he can play again," Hasenhuettl told reporters ahead of Sunday's clash with visitors Chelsea. "It's a high risk at the moment when you have an injury on a muscle you only use when you shoot the ball.
"He can do everything with running, passing the ball... or sprinting. But when he shoots the ball, we must pay attention because the tendon injury is something that can get worse.
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"We're looking at the scans and... when we see it is the moment we can try it, then we do it. I would like him back (in training) as soon as possible... maybe after the international break."

Moussa Djenepo of Southampton celebrates after scoring against Brighton during the Premier League match at American Express Community Stadium on August 24, 2019

Image credit: Eurosport

Hasenhuettl will also be without the services of full back Cedric Soares, who injured his calf during the warm-up prior to their 2-1 loss at Tottenham Hotspur last weekend.
The Portugal defender, who had to be replaced in the lineup at the last minute, will likely return after the international break when Southampton visit Wolverhampton Wanderers.
"He (Soares) really tried to play against Tottenham which maybe wasn't the best idea, but he really wanted to help the team," Saints' Austrian manager added. "He was in good shape and was looking to get back to international football.
"So he tried to do it against Tottenham but after the warm-up, the problems he had were too big. I think it will take until the Wolverhampton game for him to play again."
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