Swansea defender Joe Rodon will miss Wales' European Qualifiers against Azerbaijan and Hungary in November.
Rodon has been ruled out for at least two months after sustaining a tendon injury in Swansea's 3-0 loss to Brentford on Tuesday.
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Swans manager Steve Cooper confirmed the 22-year-old centre-back would miss Wales' trip to Azerbaijan on November 16 and the home game against Hungary in Cardiff three days later, both live on Sky Sports.
Wales need to win both games to qualify for Euro 2020 next summer and the news will come as a huge blow to manager Ryan Giggs, as Rodon has recently established himself at the heart of the Dragons' defence, winning four international caps to date.
"Joe had a knock on the ankle last week but he picked up a fresh injury on Tuesday night," Cooper said after Swansea's 1-0 win over Cardiff on Sunday.
"He's got a tendon injury that rules him out of the Wales games too. He's going to need an operation next week and will be out for a few months.
"What hurts him will make him stronger, but he was close to tears when he heard the news.
"I think it hit home when he knew he wasn't going to play. But he stood by the side of the team and didn't leave us for one minute."
Newspaper reports have linked Sheffield United with a move for Rodon in the January transfer window.