Sheffield United manager Danny Wilson admitted Yeovil deserved their 2-0 win at Bramall Lane on Saturday afternoon.
Paddy Madden fired low past George Long after being set up by Byron Webster four minutes after half-time and was then rewarded for his tenacity in the 66th minute, walking the ball into the net after catching the keeper in possession.
Wilson said: "It was really disappointing. Throughout the game, there were too many opportunities where we didn't play as well as we can.
"Our defensive work has been average at times and we never really got a head of steam up, apart from just after half-time, before we conceded a second goal.
"I thought at that point that we might just get back into the game but we gave too many chances to them. In the first-half we were second best to the ball and we always seemed to be chasing the game.
"To be fair to them, we were chasing opponents who were getting to the ball quicker than we were and that was typical of the game.
"For the second goal, I think he (Long) has made a decision to play the ball out to Marcus (Williams) and all of a sudden he's been pressed and taken his eye off the ball.
"Credit to Madden who has run about 30 yards and walked the ball in. It happens and in a key area like George is playing in, mistakes generally get punished. I'm taking nothing away from George who has been fantastic for us.
"You can make an excuse and I will make an excuse because the pitch is very difficult at the moment. It doesn't really suit us because it's really bobbly.
"It slows us down and in doing so, I think it's an advantage to the opposition. But you have to turn round and say well done to Yeovil because they haven't half worked hard. They absolutely pressed us to death for the whole 90 minutes and full credit to them."