City travel to league leaders Liverpool on Sunday.
"I don't think Pep went into [the press conference] with that in his head, I think he was just triggered by a question about the result at Villa Park and it's just come out," Murphy told talkSPORT.
"In hindsight he might look back on that and think, "I wish I hadn't said that".
"If I was him, the last thing I'd want to do is wind up the best player in the Premier League at the moment and before you play him next week.
"Mane is playing incredibly well and if it does spur him on a little bit more, then why take the risk?"