The Gunners skipper was named in the starting XI at Camp Nou, despite worries over his hamstring, but was unable to prevent a 3-1 defeat and 4-3 aggregate exit for Arsene Wenger's side.
And now he has confirmed that he aggravated the injury just 15 minutes into the match, but he played on for as long as he could before being substituted in the second-half."It was a shame because I felt really good to start with," he told TVE.
"But after 15 minutes I felt a pain and I knew it was over for me.
"The desire to play allowed me to continue and get through
but then I had to change."
Arsenal are now awaiting news of scans to the injury, but reports claim that their skipper has already been ruled out of this weekend's FA Cup clash at Manchester United.
