Trabzonspor's Nigeria international Ogenyi Onazi is set to miss the rest of the season after sustaining a ruptured Achilles against Rizespor on Sunday.
The midfielder, 25, was stretchered off on 32 minutes and faces a lengthy spell on the sidelines.
"Unfortunately Onazi suffered a ruptured achilles tendon. His season may well be over," said Trabzonspor president Ahmet Ağaoğlu.
Onazi was set to have surgery on Monday.
The Super Eagle, who has scored twice in 16 appearances this season, has been a key part of Trabzonspor's run of good form since September.
They sit second in the Turkish Super Lig table and he had been looking forward to replicating that form with Nigeria before this latest setback.
Onazi also faces a race against time to be fit for next year's Africa Cup of Nations to be staged in June 2019.
He started his professional career in Italy with Lazio, winning the 2013 Italian Cup, before switching to Turkish side Trabzonspor in August 2016.
He played for Nigeria at the 2009 Under-17 World Cup on home soil and has scored once since making his senior debut against Liberia in October 2012.
Onazi, who has 51 international caps, helped Nigeria win the 2013 Africa Cup of Nations, and played in all four of his country's games at the 2014 World Cup in Brazil.