The Terriers were desperately off the pace in losing 2-0 to their relegation rivals at the John Smith’s Stadium on Saturday.
Defeats for West Bromwich Albion and Stoke City elsewhere did alleviate some of the disappointment felt by the locals in another sell-out crowd at the final whistle.
But Wagner, when asked about staying up, said: “If we play like this seven further times this season, no chance. But if we perform like the games against Swansea, West Brom or Bournemouth then there is no doubt we can stay up.
“We have to do better, we all know that, but I am pretty confident we can do that because we have done it in the past.”
With West Ham United, Southampton and Swansea City not in league action over the weekend due to the FA Cup, Town remain three points clear of the drop zone.
“We under-performed against Crystal Palace,” added Wagner.
“We were below par. We did not want to do this, but we know what went wrong.
“If you know what is wrong, relatively easily you can deal with it. Our problem was that we were one or two yards too late.
“We were not good enough in ball possession. Palace have the pace and quality to beat you if you give them those two or three yards.
“Credit to them, they took advantage.
“That is why there is no reason to panic. Not because of the table or the results or the points we have, and do not forget we are in a reasonable position for Huddersfield Town.
“But the reason not to panic is we know what we did wrong and we have performed much better this season.
“There should not be any difference to our confidence because of this result.
“We must perform better and we have done that in the past. That is why we have collected points this season.
“The good thing is no one thought it would be an exciting season for us because everyone thought we would be far away at the bottom of the league.
“We are in a position where it is exciting.
“We take that excitement and try our best in the future.”
Match report: Page 2.