Jan Kirchhoff is on a fast-track programme to reach match fitness after playing just two minutes of competitive football for Bayern Munich this season.
Centre-half Kirchhoff yesterday became the first signing of the Sam Allardyce era at Sunderland after arriving in a £750,000 move from Bundesliga giants Bayern.
But the 25-year-old - who will not be involved in tomorrow's FA Cup third round tie at Arsenal - is playing catch-up with his fitness levels after only one brief substitute's outing for Bayern in the German Cup this season.
Kirchhoff has just returned from his winter break with Bayern too and knows he needs to get up speed after such minimal game-time since last season's loan spell at Schalke.
"I'm coming out of the winter break in Germany and had two training sessions with Bayern," he said.
"I may need some time to get fit.
"But I'll try to get on the pitch as fast as I can to help the team."
Kirchhoff's contract at Bayern was due to expire this summer and there had been interest from Bundesliga rivals Eintracht Frankfurt, VfB Stuttgart and FC Augsburg.
But Kirchhoff - who trained with Sunderland for the first time yesterday morning - wanted to test himself in the Premier League after coming up against English opposition in the Champions League.
"I have always had the dream to play in the Premier League and be part of it," he added to the club website.
"Now I've got the opportunity and chance to do this.
"I've grabbed it and I'll try to be successful in this new country.
"For Schalke, we played against Chelsea and had a very bad day and lost 5-1.
"At Bayern, we played against Arsenal and Man City.
"Those are teams with very good players and individual quality.
"It will be a big challenge for me."