If it’s bad news over the League One title winner it’s a significant blow, following his reassuring return from a five-month calf lay-off.
There are options at the back for John Mousinho, but the Pompey boss does have the option of moving into the free agent market to bolster his back line.
The Blues have left one space open in their 25-man squad to do just that, something the recruitment did last year when impacted by midfield issues.
Lee Evans arrived to bolster that department back then - here’s a list of 12 central defenders who could do likewise this time.
13. Michael Hector
Moved to Fulham for £8m four years ago, but the 32-year-old is without a club after mixed reviews in League One for Charlton last season. The Jamaican international did play international football in the Copa America and World Cup qualifiers last summer. Photo: Getty Images