Streich saw his side bow out of the competition after a 2-0 home defeat to Sevilla, condemning the Bundesliga outfit to a third-place finish in Group H.
However, the German praised their performance in the defeat - which came courtesy of goals from Vicente Iborra and Raul Rusescu at the end of each half - adding that Freiburg deserved more from their campaign.
"The team played a really good first half, but we go in behind at the break because we made a mistake and were unable to take our chances," he told the club's official website.
"Seeing the passion with which the team is working, but are not rewarded, then that hurts."
Freiburg have now lost their last four games in all competitions and will be looking to bounce back when they return to Bundesliga action with a clash against sixth-placed Schalke on Sunday.
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