With Holland currently on top of the group, it is a showdown between Japan and Denmark to see who progresses to the knockout stage, with both sides on three points.
The Danes must win, however, as they have an inferior goal difference after they lost their opener to Holland 2-0.
Martin Olsen's men hung on to beat Cameroon 2-1 in their last game, sending the Indomitable Lions out of the competition, but Sorensen is expecting a tougher contest against Japan.
He said: "We saw a bit of Japan's match against Holland, it's going to be a different game, they are a lot more organised than Cameroon, maybe not as individually skilled but they are similar to us, they work as a team.
"It's going to be a difficult game, they'll run their socks off, but it's down to us to break them down.
"They'll probably be looking for some counter-attacks so we need to be disciplined, but we also need a goal.
"We need to break them down because we need to win. I'm sure the manager will have a plan."
Sorensen, 34, admits the injury problems within the Denmark squad have been a concern but hopes the worst is behind them.
He added: "It has been a worry but everyone came through the match and in the next couple of days we need to access things.
"We need everyone fit obviously but the people who have been injured, like (Nicklas) Bendtner and (John Dahl) Tomasson, looked ok.
"Hopefully we can play ourselves into shape."
Source: Team Talk
Source: Team Talk