The Blues fell out of the top two for the first time since August 25 following their 1-1 draw with Doncaster on Saturday.
The Tykes took full advantage of that slip up, delivering a 2-0 victory over Scunthorpe at Oakwell.
As a result, Barnsley moved up to second and are now a point ahead of Kenny Jackett’s side.
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Stendel knows there’s still a long way to go until the end of the season .
But the German is adamant his troops won't surrender their berth in the automatics.
The Tykes boss told BBC Sheffield: ‘It’s a good result after 30 games.
‘There is a long way (to go) with 16 games left.
‘At the moment we’re happy and we have a lot of difficult games in front.
‘But I believe that we can save this place.’
After a 2-2 draw at Oxford United on Tuesday, Stendel was delighted his side bounced back to winning ways against the Iron.
He added: ‘It was a hard week for us with an away game at Oxford and it was a good performance from us in the second half.
‘We could have scored three or four but won 2-0 and got three points.
‘We’re satisfied with the performance. We wanted to play better than on Tuesday and had a lot of chances. I was happy with the performance.
‘Before the game we spoke about working together more without the ball and you could see that.
‘Then we had a lot of chances and had a lot of confidence with the ball.
‘I would have liked it if we scored more but we won the game and we’ll keep the goals for the next matches.’