Nasri when on his game and in the mood was world class ( seldom!) and for me a way better player than Grealsh.Yeah the attitude is completely different. Nasri could have gone on to achieve a infinitely more if he conducted himself like a proper professional. But there are similarities in the way they play and what their strengths and weaknesses are. But Jack is clearly determined to prove what he can do and test himself against the best or he'd still be at Villa.
But I disagree that Jack has improved this season. I think he's pretty much been doing what he did last season. Last night was probably the worst performance he's put in yet but he's simply been average overall.
Grealish at Villa was so overrated, I simply never got him. I watched him closely when we played against them, he was anonymous, always looked good in highlight reels , looked good in a very average team but as it stands looks to be struggling at the very highest level.