Maurizio Sarri said he was shocked by Newcastle's defensive approach as Chelsea snatched a dramatic 2-1 win at St James' Park on Sunday.
Newcastle manager Rafael Benitez sent out his injury-hit team with a massed defence often featuring all 10 out-field players.
The ultra-cautious approach worked for 76 minutes as frustrated Chelsea struggled to break through.
Sarri's side finally took the lead through Eden Hazard's penalty.
But Joselu equalised for Newcastle only for a DeAndre Yedlin own goal three minutes from full time to seal Chelsea's third successive Premier League victory.
Sarri was pleased with the way his players kept plugging away against such a conservative opponent.
"I have never seen a Rafa Benitez side play with five defenders. I think it is very difficult to play here for every team - not only us," he said.
"The match was very difficult and it was impossible to have space. We were good, better in the second half, but it was very difficult.
"We were a bit unlucky when they scored to make it 1-1."
Newcastle complained that Fabian Schar's tackle on Marcos Alonso shouldn't have been a penalty, but Sarri refused to comment.
"I don't know I was far from the incident and I am not the referee, and I don't want to be a referee either," he said.
Saluting Belgium playmaker Hazard's display in his first start of the season, Sarri added: "Eden has played very well but maybe it was better if he played for only 75-80 minutes, but (Mateo) Kovacic asked me to be replaced so it was not possible."
Newcastle, United Kingdom | AFP