Bayer Leverkusen coach Robin Dutt insists former Chelsea player Michael Ballack is an important part of his team.
The midfielder has been wearing a protective mask recently after breaking his nose but hasn't let it affect his game, scoring two goals in his last four games.
Leverkusen face Chelsea in the UEFA Champions League on Wednesday after a poor run of results for the Blues and Ballack will be aiming to pile more misery on his old club.
The Germany midfielder left Chelsea 18 months ago after his contract ended at Stamford Bridge.
And Dutt says Ballack, who may leave the BayArena on a free in the summer, is a key component of his squad.
Dutt said: "The way he's played in the last few matches and months, he's incredibly important. There's no question about that.
"In our team, there is hardly anyone who has played in the Champions League. For most players, it's new territory. It's good to have an experienced player in form.
"He's not affected by the mask - he doesn't wear it in training, so we'll decide tomorrow whether or not he'll wear it."