Purslow held his post on the Anfield board from 2009-10 and was heavily involved in the sale of the club from Tom Hicks and George Gillett to the current owners.
And he insists the club are well placed to take advantage of the new Financial Fair Play rules.
Purslow told Sky Sports News: "I think Liverpool are in a good position because their approach is utterly consistent with the theory of Financial Fair Play (FFP); namely you should break even, you should not lose money and you should only spend what you earn.
"That has been the clear philosophy of the owners since they took over at Anfield.
"I would go so far to say that there are three champions of fair play in the Premier League - Arsenal, Liverpool and Manchester United. What is interesting is who is the target of these new rules and of course the primary target is Manchester City.
"We have a situation in England where five into four does not go. We have five massive clubs operating on a global basis with very large wage bills trying to get into those four precious Champions League places.
"They will stop at nothing and FFP is another means of competition between those five rivals with the so-called fair play revenue champions on one side and more of the oligarch model - Manchester City and to a lesser extent Chelsea - on the other side. This is all about a battle to be in the top four."
Liverpool have never had a greater chance of breaking their 24-year title drought than they do this season, but Purslow - who remained at the club in a non-executive capacity until February 2011 - is adamant that it will not be a disaster if they fail to prevail come May.
He said: "Obviously, from an historic standpoint it used to be the case that winning titles was what Liverpool was all about. What has been remarkable is that, despite the lack of titles their global popularity has never waned.
"With a championship title there would be a whole new level of appeal and financial benefits, but the fans are very excited with the way things are going at the club and if they are to win the league this season, then that will just be a bonus.
"The owners would probably think that if it comes this season then it has come a little bit earlier than they would have budgeted and planned for."
The real bonus for Liverpool will be the impact that Champions League qualification will have on Brendan Rodgers' recruitment policy this summer, according to Purslow.
"The principle financial effect of this season will be that they are going to be in the Champions League next season. This will deliver an extra £25-30million of revenue," Purslow said.
"John Henry has always said his model is to spend what you earn, to invest the natural level of revenue that the club generates. The extra revenue will allow them to be a little more expansive in their recruitment.
"The agenda had moved away from who will Liverpool lose this summer to 'who do we expect Liverpool to sign now they are back in the Champions League?'
"Of course if you buy top-star players on five-year contracts and then find that you are only in the Champions League for one season then that can lead to problems. That trap has caught out many badly run clubs in the past; I don't for one moment see Liverpool falling into that trap."