Ten Hag’s team are winless in three games before facing Porto in the Europa League, having been held to a draw by Twente at Old Trafford in their opening match in the competition last week.
“Everyone has to take responsibility and that starts with me as the manager,” said Ten Hag.
“But on the pitch we have leadership skills and they have to stand up. Every game for us is important and every opponent is 100% motivated. We have to be ready to compete and fight.”
Ten Hag led the Red Devils to a third place in the Premier League during his maiden campaign in 2022-23, while they also lifted the EFL Cup and were runners-up in the FA Cup.
Last season, United came eighth – their lowest-ever Premier League finish – but signed off in style by beating Manchester City to win the FA Cup.
The Dutchman was subsequently rewarded with a new contract, which runs until 2026, over the summer and last month club chief executive Omar Berrada said he had the club’s full backing.
Ten Hag said he and his staff “talk every day” with the club’s new football hierarchy but added speaking to the club’s new sporting director Dan Ashworth is “not necessary to give me confidence”.
“We are a union and we made that commitment in the summer. We refreshed the staff and I appointed my assistants, I appointed the staff. I did this. We refreshed the squad as well,” Ten Hag said.
“We talk every day about how we can improve this club, this team, improve the processes, the procedures, the connections. That is what we talk about.”
United take on Porto in the Europa League on Thursday (20:00 BST) and travel to face Villa in the Premier League on Sunday, before the October international break.