Preston left-winger Ross Wallace received his 12th yellow card of the season in the 20th minute for a foul on Michael Morrison. The first booking of the afternoon by referee Grant Hegley of Hertfordshire.
Preston goalkeeper and Player-of-the-Year Andy Lonergan made a great one-handed save to his right from a 12-yard scissor kick by Jack Hobbs following a free kick after 31 minutes.
Wallace went down with a groin injury in the 34th minute with Preston in possession and the referee awarded an uncontested drop ball to Leicester.
Former Preston loan player Paul Gallagher punted it up field from deep into his own half in an attempt to give possession back to North End.
But the ball sailed over the back-pedalling Lonergan and into the net, the referee quickly disallowed it. Gallagher retook it with power and Lonergan tipped it on to the post.
Nolberto Solano replaced the injured Morrison in the 36th minute.
Preston substitute keeper Wayne Henderson replaced Lonergan at half-time after he sustained a groin injury.
Henderson and Elliott Ward bumped into each other and James Vaughan put the ball into the back of the net. However, the referee quickly blew his whistle and ruled out the goal.
Ward was booked in the 56th minute for a foul on Martyn Waghorn.
Andy King made it 1-0 to Leicester in the 63rd minute when he picked up the ball from Sean St Ledger, ran through the defence and struck the ball into the bottom right corner of the goal from just inside the area.
Neil Mellor and Chris Brown replaced Keith Treacy and Jon Parkin in the 65th minute.
In the 70th minute Nicky Adams replaced Lloyd Dyer.
Vaughan ran through the heart of the PNE defence but Henderson was quick off of his line and blocked the shot well in the 76th minute.
Dany N'Guessan replaced Vaughan in the 82nd minute.
Waghorn had a shot saved from Adams' cross after 83 minutes.
Preston captain Callum Davidson was named as man-of-the-match.
N'Guessan had a shot saved after 88 minutes. Three minutes were added.