Exeter director of rugby Rob Baxter accepted that his side's European campaign was virtually over as they crashed to a surprise 27-19 defeat at the hands of Gloucester at Sandy Park.
Gloucester were deserved winners with tries from Willi Heinz, Jaco Visagie and Ben Morgan. Danny Cipriani kicked two penalties and two conversions with Billy Twelvetrees adding a conversion.
Exeter's tries came from Nic White, Tom Lawday and Don Armand, with Gareth Steenson adding two conversions, but it was not enough to secure a single point so they remain at the bottom of Pool 2 with only three points from their first three games.
"The group still haven't got it mentally right around Europe yet, as today they were individually and collectively better than us," Baxter said.
"We are normally efficient with the cogs fitting in well but our set-piece didn't function and we were bitty.
"There was no clarity of thinking and our machine stuttered as we made error after error.
"Matt (Kvesic) kicking the ball away gave them a try and it took the wind out of our sails and after that there was multiple errors as we kicked the ball out on the full and our tackling was passive.
Gloucester's head coach, Johan Ackermann was delighted as he saw his side turn around a 23-6 defeat at Sandy Park only a fortnight ago.
He said: "We were much better and learnt to be more patient and today, unlike then, a few things went our way.
"We matched them for territory and possession and our set piece functioned well but the boys said it is one of the most physical games that they have ever played in.
"We started badly in both halves but I was particularly pleased that we didn't panic when things were going against us.
"The team has grown tremendously in fronting up against setbacks and the players now have more belief, as last season we conceded 50 points at Saracens in the second half when we were in contention at half-time so hopefully we are closing gaps."
Gloucester now face Exeter in the return fixture at Kingsholm, a task which Ackermann accepted would be daunting.
"If we lose next week no-one will talk about this game but it gives our guys self-belief although we will have to knuckle down as we are expecting a big backlash next Friday for they are a very good side," he added.