The injury-hit RaboDirect PRO12 champions suffered a second loss of the campaign, beaten 30-14 by the four-time European kings but while their failure to pick up at least a losing bonus point leaves them eight points behind Toulouse in the standings, Humphreys saw plenty to be proud of in his young team.
Humphreys said: "We're very proud of the boys. We could have improved on a few things tactically but we could not have improved the effort - that was as good as it gets. We had six guys making their Heineken Cup debut and I thought they were outstanding."
He added: "With the amount of set-pieces they had in our half you would have expected the score to have been heavy, but in the end I don't think it did us justice.
"We are disappointed because coming in at 12-7 at half-time we should have been in front. We created a lot of pressure and they were ragged.
"In the second half we wanted to get down their end and create some set-piece pressure but we weren't able to do that. We felt we could have a real crack and if we could have just executed better a few times it could have been a different story."
Ospreys host Toulouse next week at the Liberty Stadium fully aware that one more defeat would end their already slim chances of progressing to the quarter-finals.
Humphreys said: "This is a disappointing result but we're looking forward to next week. It's all about recovering and seeing if we can do ourselves justice in the home leg.
"We can still have a big say in this tournament. We have Toulouse to come down to the Liberty Stadium and Leicester so it is important that we do ourselves justice.
"This was a positive experience for us in terms of players coming through. We have to develop from within because we don't have a budget like Toulouse, but it was great to see young players out there coming through."