The match finished 2-2, thanks to a double from Murphy, and another from David Connolly for the away side.
A few minutes into the second half, Stanley were ahead thanks to a curling effort from 30 yards out by Murphy.
They almost double their lead instantly as Leam Richardson drove forward and fired the ball towards goal. It bobbled past the goalkeeper but was cleared off the line by Bradley.
Shortly after that Pompey were back on level terms. A long pass towards Agyemang allowed him to lay the ball off for his strike partner Connolly, who fired into the near corner first time.
With 10 minutes to go, he got his second from the penalty spot, sending the goalkeeper the wrong way after being brought down by Hunt.
Stanley were not done though, equalising themselves on 85 minutes thanks to Murphy's second goal. This time heading in from close range after a good header back across the goal.
Pompey almost took the lead again immediately after but Barcham's curling effort rebounded off the post.
They continued to push for another goal, but in the end had to settle for a point after a couple of late chances.