Sun Problem?

[BobcatJohnson]

Cant tell from the pictures, but did one of the new roots split the base of that leaf as the root was forming? That is something that can cause leaves to die off early.

[camille1585]

Given the history of the plant, to me that looks like it could just be the plant which is mobilizing nutrients out of an old leaf in order to support the new one(s) coming in. A poor root system (though improving now) means suboptimal uptake, and those smaller than normal leaves means that the plant has less 'storage' for nutrients.
If the problem stays limited to just that one leaf, (and possibly the oldest leaf under it), I wouldn't worry, as long as it is still growing roots and that new leaf.

[infinity_blues]

Originally Posted by BobcatJohnson

Cant tell from the pictures, but did one of the new roots split the base of that leaf as the root was forming? That is something that can cause leaves to die off early.

Not totally sure but I'll check that when I am home from work

[Mr.Fakename]

I am with Camille on that one. It looks like totally natural "hollowing" of old leaves.