Manchester United manager Ole Gunnar Solskjaer has warned football is in danger of becoming as physical as rugby if the current lenient guidelines are kept in place.
Solskjaer was frustrated when referee Craig Pawson's decision not to award a foul on Bruno Fernandes led to Southampton opening the scoring through Fred's own goal in Sunday's 1-1 draw.
Mason Greenwood's second half equaliser took United's unbeaten Premier League away run to 27 matches, equalling the English top-flight record.
But Solskjaer was incensed that Jack Stephens' challenge on Fernandes was not punished when it would almost certainly have been a foul last season.
Fernandes was booked for his protest and the new guidelines for referees to let play flow looks certain to become a talking point with managers.
The incident coming a day after Liverpool boss Jurgen Klopp told people to "watch wrestling" if they liked some of the challenges Burnley put in during the Reds' win at Anfield.
"If you don't get a foul, we should make sure we block the shot, put your body on the line and make sure they don't get a strike on target," Solskjaer said.
"That being said, it's a foul. He goes straight through Bruno, his hip and with his armpit and his arm across him.
"I'm not worried but we have to look at it because we can't go from one extreme of volleyball or basketball from last year and go into rugby now.
"I liked the more lenient way, it's more men's football but, still, that is a clear foul.
"That being said, you can see early on with the fans as well, it gets the crowd going when you fly into a few tackles and we did suffer a few tackles."