Vlaar set to miss four months
Ron Vlaar is unlikely to be fit until 2016, having undergone surgery to repair a torn meniscus in his left knee.
The Netherlands international's contract at Aston Villa expired last month, with terms on a fresh deal discussed but yet to be agreed after a season hit by more injuries limited the central defender to 23 appearances in all competitions.
It remains to be seen whether Vlaar, 30, will remain at Villa Park, though his immediate future will be taken up by months of rehabilitation.
A statement read: "At the end of the season a trip was arranged for me to travel to India.
"It was during this trip that I noticed something was wrong with my body, something didn't feel right. In response to this, I requested a medical examination and unfortunately my worst feelings were confirmed.
"On the MRI scan of my left knee it became clear that I had a torn medial meniscus.
"You may or may not be aware that in January I had surgery on the same injury, and after a short period on the sidelines I was back on the pitch and playing again.
"It's far from ideal if you have to undergo this procedure twice in six months, so the doctor made the right decision by drilling into my cartilage. This means that there will be scar tissue for protection, which will combine well with good musculature in the upper legs.
"So what does this means in the short term? Well, instead of two days with crutches, there will now be a four to six weeks period.
"Instead of four weeks rehabilitation, it will now take three to four months.
"On hearing this news it was a defining moment, I was stunned and I struggled to keep my composure. Even now when I think about it, the news is very hard to swallow."