Sunderland manager Dick Advocaat says he will hold a Sunday meeting with his players to find out why his side have started the season so badly.
"It was even worse than last week," Advocaat said. "We have to discuss with the players how we go on.
"We have to find the solution, because otherwise we have no chance."
Sunderland used four different strikers in Jermain Defoe, Steven Fletcher, Danny Graham and 21-year-old debutant Duncan Watmore, who scored an 88th-minute consolation with only his side's second shot on target.
By that time many frustrated fans had already left the ground early, while some of those who stayed called on chairman Ellis Short to invest in the squad further.
This summer Sunderland have signed defenders Younes Kaboul, Sebastian Coates and Adam Matthews, as well as midfielders Jeremain Lens and Yann M'Vila.
"Even this squad must be good enough to get a better result against Norwich, with five new players, but there is something wrong, that's quite simple," Advocaat added.
"It was the same in pre-season and you hoped it would change but it is not changing.
"I have an idea about it, but tomorrow we will have a meeting and they can talk and I will talk. Myself as well, I am responsible for that, no doubt."
Sunderland next play Swansea at home on Saturday, 22 August.