Defeat on Tyneside left the Blues 13 points adrift of Barclays Premier League leaders Manchester United, having played a game more, and Benitez under ever greater pressure.
However, he was refusing to be bowed by the criticism despite seeing his team fail to hold on to a lead for the second time in four days.
He said: "We are doing a good job in terms of what you can see on the pitch. The team is doing well.
"The team has a very good team spirit and that is really positive, and I am confident that we will finish in the top three. I will do well.
"What I know, what I can see is the team doing well, working hard and when we have this advantage, we have to manage in a better way."