Erik ten Hag has told his Manchester United players he will continue to crack down on squad discipline after axing Cristiano Ronaldo and dropping Marcus Rashford.
Ronaldo had his contract cancelled after criticising Ten Hag and the club in an interview with Piers Morgan while Rashford was punished for being late to a team meeting.
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Youngster Alejandro Garnacho was also sanctioned during the preseason tour in the summer and Ten Hag says he will continue to set strict rules at Old Trafford.
"If you want to develop something, if you want to create a winning attitude and winning culture you have to go this way in my opinion," said Ten Hag.
"Everyone will do it their own way but if you allow them to be ill disciplined, if you don't match the standards, values and rules we set together as a team and as staff, if you don't have that togetherness in the dressing room, then it will come back and it will blow up in your face.
"On the pitch that will happen if you do not have the discipline needed to win games. It's about big responsibility so you have to go that way."
Ten Hag told United bosses there was no way back for Ronaldo following his bombshell interview with Morgan.
Rashford, meanwhile, was dropped to the bench for the game at Wolves on Dec. 31 before coming on to score in a 1-0 win.
"If it's the right person and the right human being and the right character, they will react like this," said Ten Hag.
"Related to Marcus, I was quite convinced about it because I have known him for seven or eight months and could expect that reaction."
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Meanwhile, Ten Hag says he will guard against complacency after his team recorded a seventh win in a row against Everton in the FA Cup third round on Friday. United face Charlton in the Carabao Cup on Tuesday before back-to-back Premier League games against Manchester City and Arsenal.
"You have to be watchful," said the United boss.
"We have to keep this focus and concentration, we have to work well during the days we are training. We have to keep the focus going into games and start with the right attitude.
"When you don't do that, the level in the Premier League is that high that if you're not, you will get hammered if you don't bring that mental and physical output. So you have to avoid that by working well and keep doing the right things."