Feyenoord are likely to be without Romeo Castelen and Pieter Collen for a large portion of the season after the duo went under the surgeon's knife on Monday.
Castelen has finally gone in for surgery to correct a long standing ankle complaint, while Collen has had an operation on his shoulder.
The two are unlikely to be rushed back into action, with the Kuip club forecasting a January return to the fold.
Expanding on Castelen's problems, Feyenoord doctor Robbart van Linschoten said: "On the training ground he felt his ankle again and that made an operation necessary.
"The tendon in the ankle has been fortified, so that in the future the complaints can hopefully be prevented.
"The expectation is that after six weeks in plaster Romeo can start his rehabilitation again."
It is likely to be a similar timescale for Collen, as Van Linschoten told the club's website: "Pieter had continuous shoulder complaints, whereby his arm was dislocated several times.
"That's why it was decided to undergo surgery again."