Assistant coach Shaun Edwards has revealed he is still in "disbelief" after Wales outscored England three-to-one on tries on Saturday - but still lost.
The 25-21 defeat at Twickenham ended Wales' chances of winning the Six Nations title, although they can still finish as runners-up if they beat Italy in Cardiff this weekend.
England, on the other hand, have already secured the championship with a game to spare, and will now head to France on Saturday looking to complete a first Grand Slam since 2003.
Wales endured a dreadful first-half at Twickenham, missing 19 tackles as England surged into a 19-0 lead. Eddie Jones' side then led 25-7, before Wales managed two late tries, bringing the final deficit to just four points.
"We didn't perform well in the first half, but we dominated the second half totally," Edwards said.
"To be honest, I am still in a bit of disbelief that you can lose a game in rugby having scored three tries to one. I have tried explaining that to my mother, who is from Wigan, and she didn't seem to understand it.
"We conceded one try away against England. If you look at that stat, it is not a bad performance.
"Technically, there were certain aspects of our defence that I was disappointed with in that first-half, mainly the one on one against their numbers 11, 14 and 15.
"But statistically, one try away to England is not a bad effort. Was I happy at half-time? No, I wasn't. Did we perform a lot better in the second-half? Yes, we did.
"I am not under any illusions that we weren't on our game in that first-half. But I still can't get my head around how you can score three tries, they score one and we lose."
Asked if it was just a bad day at the office defensively, Edwards added: "It would seem that, because as a defence we are still in with a chance of conceding the least tries in the competition.
"We have conceded five, England have conceded four. If we can manage to pull off a try-less game on Saturday, the pressure will be on England to keep France out."
Wales are now turning their attention to Saturday's visit of Italy, a team that they have never lost to on home soil. Fly-half Dan Biggar believes Wales simply have to move on from last weekend's loss.
"You have to move on in professional sport, and we have a hugely important test match on Saturday where we have the chance to finish second (in the Six Nations)," said Biggar.
"It's not what we wanted, but to finish second is still a reasonable achievement. Nowhere near where we set our standard, but that's what we are playing for on Saturday and we have to make sure we give Italy full respect.
"The first 40 minutes (last) Saturday wasn't good enough. We've said that ourselves and players, coaches, the whole staff - everyone has to take that on board. We just need a response on Saturday.
"But that isn't done yet so we'll keep fighting and keep going strong until we reach our objective."