To that end, it was little surprise when Juan Pablo Angel rose like a long-haired salmon to head home Gareth Barry's cross within 25 minutes.
However, towards the end of the first half, Portsmouth got to grip with the game, Tomas Sorensen the difference as the Villa keeper kept out decent efforts from Matt Taylor and Alexei Smertin.
The second half was a different matter. Shortly after the restart, Yakubu Ayegbini headed home a cross from the left flank to even the score.
Portsmouth controlled the second half but the warning signs were their for the often fragile Pompey defence and, five minutes from time, a Barry cross pinballed off Olaf Mellberg, Linvoy Primus and finally Darius Vassell before ending up in the back of the net to leave Portsmouth deeper in the relgation mire.