The German international was rushed to hospital for emergency surgery on Boxing Day after his thigh swelled to twice its normal size. Christian initially thought he simply had a dead leg.
The elegant wing-back then embarked on a lengthy recovery programme and Glenn says it is going better than expected.
"Christian is doing very well," he revealed. "He is a little bit ahead of schedule, but it is still touch and go whether he will play again this season.
"We are very happy with the way things have gone for him."
Glenn reports that Christian Ziege is making good progress in his rehabilitation from the shock thigh injury he suffered in December.