Thomas Young's Six Nations hopes have been dashed after the Cardiff flanker was ruled out for up to three months with a torn calf tendon.
The 30-year-old limped off during the Blue and Blacks' defeat to the Scarlets last weekend, prompting fears over his availability for Warren Gatland's Six Nations squad.
Returning coach Gatland names his squad next week, with Young's name likely to have featured given his outstanding form so far this season.
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The openside has led the way in tackles made - with his 170 tackles being 39 more than any other player - and turnovers won, having won the ball back 14 times across the season so far. He also sits high in the try-scoring stakes with four touchdowns.
Young joined Cardiff from Wasps last summer in an effort to break into the Wales set-up, having won just four caps to date. The first of those were against Tonga and Samoa in the summer of 2017, before Gatland picked him to face Italy in 2018.
Wayne Pivac named him in his squad for the 2021 autumn internationals, naming him in the side that defeated Fiji, but he has yet to feature since.
Last autumn, Pivac pointed to the presence of young opensides Jac Morgan and Tommy Reffell as to why Young missed out on a place in the Wales squad. However, with Gatland back and Young in superb form, as well as Morgan's emergence as a genuine option on the blindside for Wales, it seemed likely that he would have featured in the squad this time around.
However, he will instead begin his rehabilitation after being forced off during the second-half of the defeat to the Scarlets. Two other injury worries for Cardiff, Liam Williams and Rey Lee-Lo, are going through the return to play protocols after going off with for HIAs.
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