Saturday's result was Leicester's biggest winning margin since beating Carlisle by the same scoreline in 1982.
Shakespeare welcomed the confidence it will give the players but with back-to-back away games at Sheffield Wednesday and Leeds up next, he knows everyone must remain grounded.
"We said to the boys afterwards how that had been on the cards," said Shakespeare. "You hope that if you turn in the performances, you will get a result like that.
"To score six was great and the defenders and the goalkeeper are delighted to keep a clean sheet, but everyone knows it is just one game. It is a very tough league and we know we will probably play better and not get the result we deserve.
"For the confidence, it bodes well, but we have two tough away games now."