Jurgen Klopp could face an FA charge for his remarks after Liverpool’s draw at West Ham.
The Premier League leaders dropped points for a second successive game with Monday’s 1-1 stalemate at the London Stadium despite taking an early lead.
Controversy overshadowed Sadio Mane’s opener with James Milner helping setting up his Reds teammate despite being in a clear offside position.
Klopp suggested post-match that referee Kevin Friend may have been mindful of that earlier mistake with his officiating of the second half in the capital.
He said: “I heard our goal was offside, I am pretty sure the ref knew that.
“In 50-50 situations it was always a free-kick for the other team, which was hard and did not make life easy.”
“As a human being, if I know I have made a big mistake in the first half, I don’t want to open the gap any more,” he added.
“Referees are obviously human beings, and I understand that, but I didn’t during the game because I had no clue that our goal was offside.”
The Liverpool manager’s remarks run the risk of fresh disciplinary action, barely two months since he was reprimanded for celebrating his side’s late win over Everton.
Klopp was fined £8,000 and warned about his future conduct by the FA after running onto the pitch in the aftermath of Divock Origi’s 96th-minute goal.