I think he should be tried as a ST, not a RW, as he has good off the ball movement and his finishing is good.
We should loan him. He can be a good contributor off the bench, but not with Valverde here IMO, that's the problem.
Once Valverde settles on his starting XI he rarely rotates. So for example if he settles on Greizmann--Suare--Messi as a front three the next options Dembele/Malcolm would rarely get game time.
Seeing that Malcolm is behind Dembele in the pecking order he would be in the stands for most of the season.
Until he improves his finishing he won't be one of the best players in any league.
And if he does, he can be a helpful player anywhere, even here. This is a skill that will be a make or break for him
When has a loan ever worked out for us?
Malcom welcom to Zenit.
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