The young Blues have fallen to consecutive heavy defeats in the last two games – in Matchday Two away to Hoffenheim and at home to Chelsea in the Premier League 2, conceding nine goals in the process.
With two losses from two in Group F, Tuesday morning’s European encounter is now crucial and Harsley has called for his young charges to respond with a much-improved display, by cutting out mistakes and maintaining a confident mindset.
“100%, we need a positive reaction,” he told ManCity.com. “That’s all we can work toward.
“We all know the importance of the game. Hopefully, it will carry a big significance and get a bit more out of the players.
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“It’s a bit of a trip and we’ve trained on Sunday and again on Monday, working hard, trying to get ready for the game.
“Most of the times we’ve been beaten, it’s been a flattering result (for the opposition) but on Saturday, it was another four goals conceded, which is so disappointing.
“It’s a concern. We knew how Chelsea were going to try and play. We were comfortable until the first goal went in against us – we’d had the majority of the ball.
“We just couldn’t break them down. If our final ball had been better, there were opportunities for us in that first half to go in front and it would have been a completely different game.
“It was an Achilles heel – a set-piece comes in and we weren’t willing to put bodies on the line. It goes to 1-0 and we’re still alright but then it goes to two and we’ve got problems.
“It certainly looked like heads went down. It’s not what we want to see but it’s a bit of a struggle when we go two goals down.”
With City now entering a busy and potentially season-defining period, Harsley believes the key to overturning the Blues’ form is to remain calm and return to basics.
“The games are coming thick and fast,” he added. “We don’t have much time to prepare differently but we have to try and restore some confidence.
“There have been some positives with a couple of the lads getting minutes under their belt
“We’ve got to keep giving the messages and trying to push the players. There have been some tough knocks along the way but we can’t get our heads down – we have to keep going.
“We’ll see what we get against Shakhtar Donetsk – if we can get a better result and performance.”