Bill Shankly famously used to quip, when asked what his side was for a forthcoming game: "It's the same as last season." Indeed, when Liverpool won the league in 1965/66—Shankly's second title—he used only 14 players. Even more remarkably, one of them played in only 1 game, while another made only 5 appearances.
Of course, back then, teams could name only a single substitute, who might or might not be used. (In fact, prior to the 1965/66 season,
no substitutes were allowed!) Also, the top division contained 22 teams, instead of today's 20, so that a full league season was 42 games, not 38. That season, Liverpool also competed in the FA Cup, the UEFA Cup Winner's Cup and the FA Charity Shield (they were FA Cup winners for the first time in the 1964/65 season). That season, they also reached the final of the now defunct Cup Winner's Cup where they lost in the final to Borussia Dortmund. (They did not participate in the Football League Cup that year.) I mention this because the pro-
squad rotation brigade love to point out how many fixtures teams play each year, and how tired players get. What a load of, er, poppycock!
Fact: Shankly's 1965/66 championship-winning team played 53 games that season, compared to Rodger's 2014/15 7th placed side playing 58. Not a huge difference, particularly when you bear in mind that Rodgers is able to play 3 substitutes each game, while Shanks was limited to just the one.
It must be accepted that injuries and disciplinary suspensions play a big part in team selection. Shankly was lucky that injuries didn't play too big a role in his season, but he probably made sure that his players' discipline—historically, always a Liverpool strong-point—wasn't too big a factor. But why didn't he use more players anyway? It wasn't as if Liverpool had a small squad. The simple answer is that, back then, the Liverpool management's philosophy, as it was just about everywhere else at the time, was summed-up by the old adage that you
never change a winning team.
Like many football clichés, there's an amazing amount of wisdom contained in those few words.