Sheffied United boss Chris Wilder refused to concede the argument over substitutes to Liverpool boss Jurgen Klopp, who accused him of being "selfish".
Klopp has repeatedly called on the Premier League to rethink its decision to stick with a maximum of three substitutes per game, and criticised broadcasters over hectic match scheduling that he thinks is leading to more player injuries.
The Liverpool boss stepped up his criticism after Saturday's 1-1 draw with Brighton & Hove Albion and took aim at Wilder, who had been critical of Klopp and other big club managers for demanding five substitutes be allowed again in the league.
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The Blades were against the continuation of the coronavirus-inspired alternation to the substitute rules. Many believe the rule changed benefited the biggest clubs in the leagues as it allowed them to use their larger squads to their advantage.
"Everyone has the right to defend their corner, there's 20 votes in this league and everyone looks after themselves all the way through," Wilder told Sky Sports after the Blades' 1-0 defeat at West Bromwich Albion on Saturday.
"We have to look after ourselves. I'm not going into the nuts and bolts of what was said. I've always had a huge amount of respect for Liverpool as a football club as I've consistently said and respect for Juergen as well.
"So whether it's looking after the club, whether it's selfish, there's a few other managers in there that have looked after their own club as well. I'll always look after my own club."
Sheffield United have just one point from their opening 10 league games after an impressive start to their return to the Premier League last season.
They face Leicester City next weekend.
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