The Tigers went down to a 3-1 defeat at Oakwell and McCann was disappointed with a lack of control in his team’s play.
“I’m disappointed for the travelling fans really because we’ve brought a big following with us and we haven’t performed,” said McCann.
“We’re always honest in our assessment and Barnsley deserved to win. We didn’t pass the ball and we looked rushed in everything we did. Credit to Barnsley because they pressed us, but we didn’t show any calmness or control in our play and we got what we deserved.
“It was a frustrating game for us. We’ve been in good form and hopefully this is just a bump in the road. It’s a big bump because we didn’t perform, so we’ll have to take a look at it in terms of the areas that we can improve on.
“We’ve got an honest group and they know that we weren’t good enough in possession here. That has cost us.”
The one positive on the afternoon was a first senior goal for Academy product Keane Lewis-Potter and McCann was pleased for the teenager.
“I’m pleased for him because he could have had goals against Middlesbrough and Preston if the passes had gone his way after taking up good positions,” added McCann.
“For him to get on the scoresheet today is great because he is a local boy and it will mean a lot to him.
“We’re really, really pleased for him.”