Mo Diame's 72nd minute strike long-range stunned Wednesday and decided the contest on a day in which the dynamic football displayed by Carlos Carvalhal's side throughout the campaign, disappeared.
Loovens, like his team mates, was distraught afterwards and admitted it was a difficult result to take.
It was a brilliant season but in the end we are empty handed. It''s hard to swallow of course but that's football as well sometimes, it's not all positive.
"We have to make sure we keep this feeling and take it into next season and make sure it doesn't happen again."
He added: "We weren't really ourselves today."
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