Poyet now wants his side to be ruthless at the back as they look to secure their status in the top flight.
"To win the quantity of games we want to win this season, I think that defence is the key to it," the Uruguayan told the Sunderland Echo.
"Some people might say conceding a goal a game is okay - especially in comparison to many how we have done per game previously. They may even be right.
"But personally I think it is too many. I want to and I need to, see more clean sheets from the team."
Sunderland continue their Premier League campaign on November 23 when they travel to Stoke City.