Following a six-year, trophy laden spell at Arsenal, Pires left the English capital to join La Liga outlift Villarreal in the summer of 2006, plying his trade there for four more years during his playing career.
The ex-midfielder’s former clubs are now set to battle it out on Thursday in the first leg of a Europa League semi-finals tie at Etsadio de la Ceramica and he is eagerly waiting for the clash.
Gunners legend Pires is of the view that Villarreal have an edge over Arsenal in the tie as they are managed by Emery, who is vastly experienced in the Europa League, lifting three trophies in a row with former club Sevilla.
Asked who he feels are the favourites to progress into the final among Arsenal and Villarreal, Pires told Spanish daily AS: “It is difficult to give a favourite for the semi-finals.
“I would say 50-50, it is difficult to get it right.
“I think Villarreal have an advantage because they have Emery, a coach who has done very well in this competition.”
However, Pires admitted that Arsenal are more familiar with big games and thus will be more accustomed to handling high pressure situations when compared to the Spanish outfit.
“To reach a final you must not let the pressure get to your head.
“Maybe Arsenal have an advantage in that, since they know what it is [like] to play [in big games] and handle that pressure better.
“Villarreal are afraid of what has happened before, something that can take its toll on them.
”But Villarreal this time [around] have experienced players that can help them a lot.”
Emery also had a stint at Arsenal was shown the exit door after 16-months in charge with Mikel Arteta replacing him at the Emirates Stadium.