Already in the second minute, Mikael Ishak, 29, played up to Lech Poznan's lead goal scored by Michal Skoras.
Villarreal, who reached the semi-finals of the Champions League last season, then quickly made it 3-1 with three quick goals before the break.
But then Ishak stepped forward.
Directly in the second half, Lech Poznan received a penalty and it put Ishak in the middle of the goal.
A quarter of an hour later, Ishak was nicely freed and then the Swede ice-cold rolled in 3-3.
A point away from home would have been a huge success for the Polish side, but in the 89th minute Villarreal equalized through Francis Coquelin.