The former Arsenal and Celtic striker has been linked with a loan move to Carrow Road with the Canaries struggling near the foot of the Championship table on the back of a goal drought.
Meanwhile, Norwich captain
Grant left the club earlier this week after a disappointing start to the season and Shackell claims he and his team-mates let the manager down.
"He was a nice man and I got on with him well as a lot of the boys did, there is a general feeling of disappointment," he told the club's official website.
"We let him down - we've let him down the most of the season to be honest.
"We shouldn't be in the relegation zone with the squad that we have, but we are and it's not good enough from our point of view."