Liverpool goalkeeper Alisson was critical of both teams after his side fell 1-0 to visiting Nottingham Forest at Anfield on Sunday.
Callum Hudson-Odoi's 72nd-minute goal was the difference between the two sides as Forest claimed a famous victory more than 55 years in the making.
The result means the visitors ended a streak in which they failed to win every league match at Anfield since 1969.
Speaking afterwards, Reds goalkeeper Alisson said it was obvious that Forest were determined to defend at all costs.
"It was a shame, losing points at home is not good at all but the opponent today only wanted to defend and play for the long ball," he told media following the match.
"We gave them that too easily when they scored, it was poor defensively from us.
"We couldn't create much, we had a lack of quality today, we needed more energy. It is three points we have lost today unnecessarily."
While critical of Forest's strategy, Alisson also gave them credit for executing it well enough to earn the win.
"All the opportunities we had were not clear enough and they defended great, they threw themselves in front of the ball," he said.
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