Had he lived?

Hello Friends:

I would like to know the appropiate spanish translation for the last part of this sentence, I found it in a novel book:

" It is true that Ross was an athlete of above-average ability. His best sport was baseball. Dick O’connell has indicated that Ross would have been offered a fairly large bonus for signing a contrat, had he lived."

If I can deduce the meaning of that final sentence, I’d like to hear the grammatical explanation for this, and when its the appropiate time for using it.

Thank you

Sorry for my gramatical mistakes, if any.

In some clauses that should begin with “if”, we sometimes choose to invert the subject and auxiliary verb the same way we do in a question.

“Had I not seen it, I would never have believed it.”
“He could have been one of the victims, had he been at home.”

We invert the subject and auxiliary in a similar way when we start the question with some kind of negative adverbial expression:

“Never did I try to contact him.”
“In no way did I intend to insult her.”
“Barely had I arrived when the electricity went out.”

This word order is relatively common, but not the most common for that type of statement.

Thank you, for your complete answer friend Jamie…
Now I understand that strange, for a non english speaker, strange gramatical construction.

thank you again, for your time and interest.

You can find two or three lessons on this in the Cambridge book “Grammar in Use - Advanced”.