Robert Pires admits his substitution during the 2006 Champions League final made up his mind to leave Arsenal.
He said: "When we played Barcelona in the 2006 final Jens Lehmann was sent-off after 18 minutes.
"I made way for Manuel Almunia. When I saw the board with the number seven I couldn't believe it. It meant a lot of things, not least that I no longer had the full confidence of Arsene Wenger. After that I couldn't stay at Arsenal.
"It was a bad night for me especially as we lost the final 2-1. I signed a two-year contract with Villarreal that summer. People couldn't understand why but when Arsenal played them in the semi-finals I could see what the club had.
"For Villarreal to be in the Champions League again means a lot. These days we can play against the biggest clubs in Europe, at the highest level without fear. We've proved that against United when we drew at Old Trafford last month.
"I love playing against United. It's fast football, back and forth. When I played in England it was the type of football I liked a lot."