Tomas Kalas has appeared to have undergone surgery on an ongoing groin issue that is likely to rule him out for the rest of the season.
The centre-back hasn't featured for Bristol City since the 2-1 home defeat against Birmingham on March 5, having been forced to sit out of the past five matches.
Nigel Pearson initially suggested he was a doubt with a groin problem before the victory over Blackburn on March 12. He later admitted that Kalas has reached his saturation point, laying blame to the amount of football he has played over the past two to three years.
The City manager also confirmed Kalas had been playing through the pain "for a while" and was happy to give him the opportunity to fully recover previously hoping he would be ready to return after the international break.
However, it soon became clear Kalas' injury is probably more serious than initially feared, particularly after he failed to return to the matchday squad following the two-week break last month.
Pearson didn't go into detail on an update of his situation before the Peterborough game, only ruling him out of action, but an image posted to his Instagram page on Monday afternoon provides extra detail on the severity of the problem having undergone a scheduled procedure.
It showed a hospital tag around his wrist with his name, date of birth and the name of the medical specialist Professor Ernest Schilders.
A look into the website of Ernest Schilders reveals he "combines expertise in medical conditions of the soft tissues around the hip and groin with extensive hip arthroscopy experience. Hip arthroscopy is a highly specialised and technically demanding procedure that should only be done by surgeons with extensive experience."
It adds: "Professor Ernest Schilders is the country’s leading expert on adductor problems in athletes and has spent more than 15 years researching on this subject. He has treated players from the majority of Premiership and Championship teams."
The image has laid doubt as to whether Kalas will feature again this season with just five matches remaining before the curtain closes on May 7 after the trip to Huddersfield. Pearson has previously admitted that there is no timeframe on the player's return to action.
After joining permanently in 2019, Kalas suffered a hamstring injury and then knee tendinitis limiting him to 23 Championship appearances. Since then, he played 40 times in the league in the following campaign and another 35 matches this time around.
Last month, Bristol Live crunched the numbers to prove Pearson's comments that Kalas required a much-needed rest, with goalkeeper Dan Bentley the only player among the squad to have played more minutes.
Pearson previously said: "He needs time to recover basically. It's an overuse injury essentially. When you're dealing with international players who have played continually for two or three years without a significant break, psychologically it can be a big hurdle to get over but when you're a physical player like Tomas, the wear and tear side of it certainly comes into play.
"And to be fair he's played through quite a lot of pain and discomfort for a while, and it was the same last season. Every player gets to a saturation point, and it's good to give him the opportunity to recover."
Whether the defender will remain a Bristol City player by the beginning of next season remains to be seen but with a contract expiring in 2023 and as one of the club's highest earners, the Robins may be forced to cash in this summer or run the risk of losing him for nothing in just over 12-month's time.
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