Reina says it will take some time for the players to adapt to the new style of football and has asked for patience as the team works on this.
"When you have so many changes and move in a new direction under a new boss, things don't happen instantly. It can take between three and six months before you see improvements. Honestly, the quicker we adapt and improve as a team the better it will be for everyone," said the keeper.
"That doesn't just happen overnight. Each of us has to adjust to working in a new way. For me, I'm working in a slightly different way. It is an English style of goalkeeping coaching. With the passing of each day I get used to it and what the manager wants. It is the same for all of us. We need to be patient. Some people expect miracles. Football doesn't usually work like that.
"People who criticise us about it should look at the fixtures we've had. It's been a difficult start. Arsenal at home and then going on to play Manchester City, Manchester United and Birmingham City away was never going to be easy.
"Against Arsenal we were a bit unlucky and could quite easily have won the game even though we had 10 men for a long time. The away games have not been easy. Not many teams will go to the City of Manchester Stadium, Old Trafford or St Andrews and win. Those three teams have very good records at home."