The 31st Premier League season begins earlier than usual - Crystal Palace face Arsenal on Friday - as football tries to fit in a winter World Cup.
BBC Sport explains all...
New rules
The biggest change is that each team can make five substitutions a game, up from three.
The Premier League brought the rule in for the remainder of the 2019-20 season when football returned after the first Covid lockdown in 2020.
While most of Europe's other leagues - and Uefa competitions - kept five subs, English football went back to three.
Now five substitutions will be allowed from a bench of nine players.