Possible Clues:

• Recognised it might be novel to the listener
• "... Yorick! I __ him, Horatio": Hamlet
• ''I ___ it!''
• Had more than a gut feeling
• Got the picture
• Was acquainted with Ken playing centre-forward
• Was acquainted with Steinbeck's last novel
• Pink "Who ___"
• Understood Kay used the opposite
• Didn't doubt a bit