Club chiefs are also concerned at the form of two of the summer signings – Timo Werner and Kai Havertz.
Following the loss to City, Lampard bemoaned errors from his players and said City showed the level he wants his team to get to in the future.
Lampard told BBC Sport: “If you want to reach the top level which City have been for a few years now you have to accept the pressures.
“The second half we competed but at 3-0 the game was pretty much done.
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