The 25-year-old goalkeeper has had to compete for his first-team place since arriving from Lyon, leading to questions being raised about the manager's handling of the situation.
After electing to hand a start to the French international ahead of veteran American Brad Friedel for the game at Carrow Road -- Friedel rarely plays in cup matches -- Lloris failed to deal with a Grant Holt header, leading to Simeon Jackson's winner near the end of the match - but the Portuguese boss refrained from blaming the 25-year-old for the mistake.
"He did extremely well in the game. He had a good solid performance. It is difficult for goalkeepers in situations like these," Villas-Boas told reporters.
On the topic of the team's shaky defense, though, Villas-Boas sounded more worried about the lack of form from his back four, insisting that the unit has to improve.
"It is obviously something that is in our mind at the moment," Villas-Boas said. "It is obviously difficult, but the further you train these situations sometimes the worse it becomes. You cannot match the emotion and concentration players face during the game. We obviously have to do better and try to improve things for the next game. It's a pity to see the game slip from our hands. We had a good performance."