Preston were very grateful to Norwich for two own goals in the first half.
Brett Ormerod had a 12-yard header saved by Robert Green in the second minute following a free-kick by Preston captain Graham Alexander.
Leon McKenzie had to be replaced after 11 minutes after he came off worse in a challenge with Claude Davis and he went off holding his back to be replaced by Jonatan Johansson.
Jason Shackell bulleted a header into his own net from a Paul McKenna corner as Preston went ahead on 20 minutes.
Adam Drury was booked for fouling Ormerod after 25 minutes and Brian O'Neil looked to have injured his knee and was replaced by Chris Sedgwick a minute later.
Simon Whaley fired over a dangerous cross and Marcus Stewart slid in with Gary Doherty to gift Preston a second with another own goal after 38 minutes.
Tyrone Mears hit a 30-yard shot from the right channel just over the bar and Dave Hibbert headed wide of the right-hand post from an Alexander cross.
Substitutions followed and McKenna had a 20-yard shot which went wide of the post, but in truth it was a dull second half after the dramatics of the opening period.