The 31-year-old, his club's top scorer for the past three seasons, has started in each tie of the Premier League outfit's 10-match unbeaten run but was forced off in the closing stages of Saturday's 2-1 victory.
However, despite manager Chris Hughton expressing his worry after the clash, the forward took to Twitter to reassure fans that the damage is not too serious - although the club are expected to announce the official results of testing later.
"We will find out about leg today sometime," Holt wrote on Wednesday. "Not as bad as first thought but we will wait and see."
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Their fine run of form has seen them propel themselves up to eighth in the Premier League and Holt feels that his team have proved their critics wrong after a tough start.
Speaking to Sky Sports at the Norfolk and Norwich University Hospital, where he was handing out gifts along with Robert Snodgrass and Alexander Tettey, he remarked: "At the start of the season a lot of people were writing us off, saying Norwich weren't doing this, weren't doing that, that we were one-hit wonders.
"I said then it was going to take time, people had to get used to what the manager was trying to do.
"We are a little bit more defensive this year, a little bit tighter. We conceded a few against Liverpool and Chelsea and we sorted it out.
"Now everything has clicked and the lads are chipping in with goals left, right and centre. The team is performing and we are at a level where everyone knows what each of us are going to do. As soon as it clicked I think everyone could see we are a very tough side to break down with the quality we've got."