There is no opportunity to win against malzahar.
You cannot poke him down until he is low enough and has to retreat because of his bullshit free passive shield.
You cannot outpush him when he can just EW the wave and have it all gone in 3.5 seconds.
You cannot cleanse his ult to escape when you are being engaged on.
You cannot rely on the malzahar being incompetent/making mistakes when his champion virtually requires 0 thought and his kit is incredibly forgiving.
He is going to perma-push the wave without interacting with you and wait until his jungler comes, then he is going to press R on you (flash if needed) and you will die. This will happen over and over again until your team surrenders at 24 minutes or they push down your nexus at 27 minutes.
Simple.
you rang?
Okay okay I know his shield only blocks damage and doesn't reduce the damage you do on first hit by 80% but still :x
or
when against 
or Vladimir
against him.
If he is a second pick , then at least you didn't get hard countered by an assassin.
I have a separate pool for first pick champs where I try to look at team comp.
: Oh, Malz has a passive? What are voidlings? You mean free gold with one Q?

or just dont 1v1 him cause his ult is basically auto win 1v1 unless they are super behind or diddint cast any spells before it.
you can get out of it but it does little to no damage so you just end up wasting the thing if they can escape it while