The Black Cats slipped to 19th place in the Premier League table and four points adrift of safety without kicking a ball on Saturday as Crystal Palace, West Brom and Cardiff all picked up points.
As a result, they will remain inside the relegation zone even if they do record just a second home win in nine attempts in the league against West Ham on Monday evening.
However, Oatway insists manager Gus Poyet and his players and staff did not need a spirited second-half display in a narrow defeat at Liverpool last Wednesday night to persuade them that they can stage a rescue mission.
He said: "As a management group, we have not stopped believing and we won't, so it's not even worth asking us as a management group, that side of it.
"But for the players, it was a good second half, mainly, against Liverpool. We created some stuff.
"But it's not been too bad overall since we got here. We have seen it become gradually better performance-wise, more understanding of how Gus wants to play, how we want to defend, so it's not only the second half at Liverpool.
"For the last five and a half, six months we have been here, it's been gradually getting better.
"You still get knocks within that, of course you get your knocks and you get your beatings and that side of it.
"But that's the nature of where we are in the league."
Sunderland have games in hand on all their rivals, but face a series of difficult fixtures as they embark upon a crucial nine-match mini-season.
Trips to Tottenham, Manchester City, Chelsea and Manchester United suggest they will have to collect the bulk of the points they need on Wearside, and that means clashes with the Hammers, Cardiff, West Brom and Swansea, who all currently occupy places inside the bottom eight, have assumed even greater proportions.
However, only Stoke have left the Stadium of Light empty-handed in a league game since title challengers Manchester City lost 1-0 in the north-east on November 10, and that needs to change and change quickly.
Oatway, who saw the Black Cats held to a 0-0 draw by Palace last time out on their own pitch, admitted: "Without a shadow of a doubt. I know the away games are so tough, but we need everything.
"We need to try to claw points however we can, especially at home with the games we have got and the teams we have got in and around us.
"We need to turn, for example, the draw against Palace, into wins."
Striker Fabio Borini returns to the squad after missing out against parent club Liverpool under the terms of his loan agreement.