Arsenal captain Cesc Fabregas wanted to play through the pain barrier against Porto, but took the advice of doctors in a bid to return to action at the weekend.
The Spaniard sustained a hamstring injury against Burnley last Saturday and has been ruled out of Tuesday's UEFA Champions League last-16 second-leg clash against Jesualdo Ferreira's side.
Arsenal trail the Portuguese 2-1 from the first leg and so are desperate to have Fabregas available for the crucial return meeting at Emirates Stadium.
But the Gunners will be without their inspirational captain, much to the 22-year-old's disappointment.
Fabregas said in The Sun: "I wanted to play but the doctors recommended I rest and avoid any risk.
"I am sad to miss out because Porto is important to us. I will suffer far more than usual, having to watch from the side."
Scans have revealed that there is no major damage and there is a chance Fabregas could make his comeback against Hull City this weekend.
William Gallas is also struggling with a calf injury after manager Arsene Wenger admitted he pushed the defender too hard in training.