When Sourav Ganguly was first appointed the captain of the Indian team, not everyone was convinced he was the best man for the job. The Indian team - and the entire cricketing fraternity - was just picking itself up after the match-fixing imbroglio, there was mistrust all around, and the captain's job seemed the least attractive it had been in a long time.

Not everyone was convinced that he was the right man for the job too. At that time, Harsha Bhogle had written that throughout his life, Ganguly has had to prove people wrong, and throughout his life he has done exactly that. At that time, Bhogle was referring primarily to his selection in the Indian team - which was widely criticized in the media - and his subsequent century on debut, which silenced his critics.

Could you please explain to me the emboldened parts?

Though I guess it as "captain's job was the very less attractive since very long time".

Source : http://www.cricbuzz.com/cricket-news/25143/Ganguly-roars-back
Yes you are with you thought/guess. As you have written it the grammar is incorrect where as it is correct above.
No, you wouldn't insert an "as" there. You could think of the phrase as:

1. The captain's job seemed the least attractive (that) it had been in a long time.

In other words, if you were to assess the attractiveness of the captain's job over a certain period of time, you would find that it was least attractive at the time in question.

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Thank you Dave Phillips.

But I think "as" is needed there like " least attractive as it had been in a long time". Now it sounds some sense to me.

Am/Aren't I correct?

I also doubt if "am I" or "are I" is correct here.
 MrPedantic's reply was promoted to an answer.
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