Michael Duff admitted his Barnsley players were outfought and outrun in their 3-0 FA Cup loss at Derby County on Sunday.
They fell behind to penalty just before the break then lost the ball twice just outside their box for the other goals.
Duff said: “We had a good 15 minutes then got outfought and outrun. We lost every dual and every header. We gave poor goals away. So it’s not a great combination which is why we got thoroughly beat. It’s not very often we have to dig them out.
"But we can’t get outrun. We have a young team but Derby were hungrier than us. They wrestled the game away from us by being more dogged and determined.
“Sometimes you have those days. I keep flipping from frustration to anger. I don’t think it’s through a lack of application. Last time we got beat 3-0 before this week was Wycombe (in August) and we got beaten up. This time we didn’t turn into individuals. It was basic decisions and simple passes. We never kept the ball well enough. We’ll dust ourselves down and go again.”
Tom Edwards picked up an injury just before the opening goal. Duff was not able to reveal any details.
The first goal was a penalty on the stroke of half-time for a handball by Matty Wolfe. It was the fourth spot-kick awarded against Barnsley in four games. Duff said: “We have an issue with the penalty again. The referee said Wolfie’s arm is in the air. I have watched it back and can’t see it. There were no appeals so we were surprised when he pointed to spot. We can’t hide behind the referee because we weren’t good enough but I’ve never seen four penalties in four games and two of them were questionable to say the least.
“We think the second goal is offside. He (Tom Barkhuizen) has come from four yards offside. I am not sure how the referee and linesman can determine where the ball has come out of a 50/50 tackle.”
It was a second successive 3-0 defeat after Monday’s loss to Bolton Wanderers following Mads Andersen’s early red card.
Midfielder Herbie Kane added: “We were poor in and out of possession. It’s disappointing because we work hard in training.
"We started well and had chances but then we came off it. We didn’t do the simple things well and got punished by a good team.
“If you look at the last 3-0 and this one it is completely different. We can take losing last week in the way we did but today was unacceptable.
“The FA Cup is one you want to get through in and draw a big team. We didn’t give ourselves that chance.”