Roberto Martinez was frustrated that Lucas Leiva was not shown a second yellow card in Everton's 1-1 draw with city rivals Liverpool.
After picking up a yellow card in the 69th minute, the Brazilian avoided a second booking from referee Martin Atkinson despite cynically bringing down James McCarthy to end an Everton break.
The controversial decision left the former Wigan Athletic boss confused and disappointed as he felt Lucas should have been punished for his calculating play.
"I don't understand the decision. I thought Lucas was very, very clever," Martinez said in his post-match press conference.
"He was a major part of this Liverpool side to stop our counter-attack and he did that really well. He got booked for one of those and his technical fouls were very clever.
"But the second one was from behind - he pushes his luck and he should have been given another yellow card."
Although Lucas remained on the pitch, coach Brendan Rodgers quickly substituted him for Joe Allen.
However, Martinez enjoyed the performance from his side - reserving special praise for Phil Jagielka - and also Romelu Lukaku, who scored the equaliser in first-half stoppage time to cancel out Danny Ings' opener.
"Phil Jagielka, in my opinion, has been the best centre-half in the Premier League for the last 12 months and his relationship with the young Ramiro Funes Mori was outstanding," the coach added.
"Tyias Browning and Brendan Galloway and our whole back four were outstanding, marshalled by keeper Tim Howard. The senior players led very well.
"The hold-up play from Romelu was the strongest we have had in an Everton shirt. Everything came from him with his back to play."
