Rublev didnt look fresh. Yesterday he was hitting winners left and right, albeit against not so good showing by Dzumhur, but looked without steam.
As for his whining, i mean tennis is an emotional game, not everyone can control emotions equally, so i think he should be given some slack there. He wants to win, but when u dont nerves get the better of you sometimes.
Plus all the players of all level sometimes love to throw the racquet, get some steam out of your system