كتب : Amro Hassan
Giorgos Karagounis broke the deadline in the 57th minute, before Giuseppe Rossi saved the tie for Villareal with a penalty-kick nine minutes later
Villareal wasted a number of real opportunities during the first-half where Panathinaikos keeper Mario Galinovic was alert on a number of occasions to deny the hosts.
In the fourth minute, a Marcos Senna cross found Angel and the latter cut inside before his powerful shot was parried by Galinovic.
Fifteen minutes later, Senna's brilliant through ball released Rossi through but the Greek champions were saved by a last-ditch tackle from Giannis Goumas.
In the second half, Karagounis punished Villareal for wasting their first half chances by putting Panathinaikos ahead on 57 minutes.
The former Inter man darted his way past the Villareal midfield before firing a shot into Diego Lopez's top corner.
Henk Ten Cate's men could have double their lead when Vangelis Mantzios found himself clear on Lopez thanks to some dreadful defending from Villareal.
However, the forward's shot was brilliantly kept out by a Lopez save.
In the 66th minute the Yellow Submarines were grateful that Pires was brought down in the area by Jakub Wawrzyniak.
Rossi stepped up confidently to convert from the spot and equalize for Manuel Pellegrini's team.
On 71 minutes, Pires led a dangerous attack from midfield and passed towards Angel, the latter's ball was missed by Cani before Rossi couldn’t get his shot in.
In what proved to be the game's last chance, Rossi could have added a second four minutes from time, but the Italian's shot went inches wide of Lopez's post.