The Nigerian midfielder, who was celebrating his 21st birthday, was shown a second yellow card for diving in the 61st minute.
While Christian Benteke scored in the 19th minute, Wilfred Zaha double the lead in the 40th minute and Bakary Sako made it 3-0 94th minute.
Reacting to the outcome of the game, Puel admitted Leicester were not at their best.
“A lot of things were missing today, it was not a good day for us.
“From kick-off, we did not have good intensity and could not find a solution. Our play was too slow against a good team with a strong defensive unit and we needed more quickness and quality in the play. Today it was not possible, was it tiredness or something else?
“The red card prevented us to try and come back in the game. Without Wilfred Ndidi, it was difficult to recover the ball and put Crystal Palace under pressure.
“I did not see the two incidents but he did not make too many faults in the game and was sent off. It was not our day and not a good game for us. Palace deserve the result, they played with desire, togetherness and quality. We did not deserve a win.
“It was not a good start and then we knew we have to play a lot of games and we have a short space of time to recover, it is the same for other teams. We need to come back with a strong spirits.”