Nigel Davies was left frustrated after watching his Gloucester side endure a shock defeat in the Heineken Cup to Edinburgh on Sunday.
The Scottish outfit dealt Gloucester's hopes of reaching the knockout stages a significant blow by winning 16-10 at Kingsholm.
"It is very frustrating that we couldn't back our performance up from last weekend," Davies, Gloucester director of rugby, told reporters. "We didn't manage the game at all well. Conditions dictated that you had to play in a certain way, and we got it badly wrong. Our discipline let us down as well, and it fed Edinburgh. They played the conditions better than us.
"We were buoyed by last week's performance and result, but we are still not in the groove and rhythm of winning games, and you have got to eke out wins however you can. In terms of Europe, all is not lost, although this is obviously a huge setback for us. First and foremost, we've got a big week ahead of us in terms of getting our domestic season up and running.
"Field position was the big thing for me today. You are not going to score 60m tries on a day like today, and Edinburgh ground out the win. They stuck to a pretty focused game plan. The top teams know how to eke out wins, and we are not in a rhythm at this moment in time to do that. These players are good players. It's a mental thing right now."
Gloucester are now five points adrift of leaders Munster in the pool with two games left to play.