Answer: No, this was merely Carl's opinion.
Step-by-step explanation:
Labelling a statement as an opinion generally protects the person who said it from defamation suits however this is not always the case.
If the opinion is based on disclosed and well known facts, the action is free of defamatory or libel charges.
This seems to be the case in this scenario as his column seems to be based on the performances for the year.
Bottomline is, Stella cannot sue Carl for libel as it is his opinion.