Joe Allen is out of Sunday's 2018 World Cup qualifier against Georgia in Cardiff, Wales manager Chris Coleman has confirmed.
The Stoke City midfielder scored with a stunning long-range strike in their 2-2 draw in Austria on Thursday.
But he came off after the break with a hamstring injury and a scan later underlined the extent of the injury.
Wales are already without Arsenal midfielder Aaron Ramsey, who also has a hamstring problem.
Defender Neil Taylor described Allen's absence as a "massive blow".
Coleman added: "Have we got enough to get a result on Sunday without Joe Allen?