Everton's Ben Godfrey is expected to be out for about three months after suffering a fractured fibula against Chelsea on Saturday.
The 24-year-old England defender will now begin rehabilitation after undergoing surgery on Monday.
Team-mate Yerry Mina sustained an ankle ligament injury in the second half of Saturday's 1-0 home defeat.
The Colombia defender, 27, will see a specialist this week to discover the full extent of the problem.
- Everton defender Godfrey fractures leg in Chelsea defeat
- You can now get Everton news notifications in the BBC Sport app - find out more
- Our coverage of Everton is bigger and better than ever before - here's everything you need to know to make sure you never miss a moment
- Everything Everton - go straight to all the best content