Hawthorn defender Josh Gibson will miss the next 10 weeks of the AFL season due to a pectoral tear.

Gibson sustained the injury in a marking contest against Sydney last week and underwent surgery on Thursday to reattach the tendon to the bone.

The 30-year-old is likely to be sidelined until August and his absence will further test the reigning premiers’ depth.

Sam Mitchell (hamstring) is still seven weeks away from returning, while Brian Lake (calf) and Cyril Rioli (hamstring) will miss at least another three weeks.

The Hawks will face in-form Port Adelaide on Saturday week minus five of their most important players, with Jarryd Roughead suspended for his bump on Ben McGlynn.

If Gibson misses the next 10 rounds, he will have five matches of the regular season to prepare for the final stages of the Hawks’ premiership defence.

“This is obviously very disappointing for Josh but he’s a player of great character and will approach his rehabilitation with the highest level of professionalism to ensure he can have an impact in the back end of the season,” Fagan said.

“Our initial thoughts were that Josh had heavily corked his shoulder as he still had full strength and movement during testing.”