The sentence could be rewritten as:
- he could not be selected, if it had not been for his friends
So it's a conditional sentence that uses the inversion to replace "if" in the if-clause (it is completely correct). As in:
- Were I more intelligent, ...
As far as the meaning of this sentences is concerned, the if-clause means more or less this:
- ..., if my friend hadn't helped him out / advised him / supported him.
I would be happy to hear from you again.
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The sentence could be rewritten as:
- he could not be selected, if it had not been for his friends
So it's a conditional sentence that uses the inversion to replace "if" in the if-clause (it is completely correct). As in:
- Were I more intelligent, ...
As far as the meaning of this sentences is concerned, the if-clause means more or less this:
- ..., if my friend hadn't helped him out / advised him / supported him.
I would be happy to hear from you again.