well, my opinion about buying diego lopez:
diego lopez has been one of the most constant performers in the last 7-8 years for sure. he was wc in maybe 2-3 years but in all other seasons he was very very good. he could drop in performance tomorrow or he can perform like this for 5-6 more seasons, nobody knows. look for example for de sanctis and roma. he is almost 38 and 1st gk for them. or buffon or someone else. you can't know for sure.
but the promising fact is his stability over the years and having no major injuries during that period.
he is the goalkeeper that made iker ( nobody can disagree that he is at least top 5 gk in the last 8-10 years ) the 2nd gk in real madrid. again, their own youth player and a fan favorite in real madrid where every loss is a greek tragedy, a place when the level of pressure is the highest. and he put even a wc perfomance season.
so, he mus be very confident and stable in the head.
and we need just that. he are in a turmoil , coming of 3 straight bad seasons and trying to make a team from scraps and "start a new cycle". stability is one of the things we need the most. a constant presence. and i don't know how many keepers is better than diego lopez for this.
carlo's number 1 gk trainer, de vecchi ( he was in milan for like 20 years, since sacchi's years ) said he is ultrac ompetitive, durable, true proffesional and a good person and that milan made a hell of a buy.
so, this is coming from his trainer that works with him everyday.
he is very good at set pieces, which were killing us for years.
he doesn't rely so much on speed and reflexes because he can pull out a save with positioning and size.
i think this is a very nice buy considering we don't invest anything and don't play champions league. maybe 2,5 m + bonuses for 4 years is too much but maybe he will be worth it, or even more, we will see.
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on the other hand, you have perin that costs like 12 m euros at least. young and maybe future number 1 keeper for italy. maybe.
he has awesome reflexes and can make super saves but he is very inconsistent. and this is milan. always high pressure and it is easy for a young gk and every young player to subdue to this pressure. and then you have a young keeper that you have payed big bucks doing only damage.
how many top clubs has that young keepers ? chelsea - courtious ( super talent, 2 levels above eveyrone ), chech was also. de gea.
but on the other side - hart lost his place in man city, polish guy in arsenal, handanovic over bardi in inter, etc.
maybe we will take perin in a couple of years but if lopez continues his form from madrid or even little less we made a great buy which will pay out with dividends in the upcoming seasons ...