Lampard's injury gives Ballack the chance to relaunch Blues career

The Blues manager had previously refused to rush the German back into action after eight months spent recovering from a double operation on his ankle.

Ballack was frustrated that his final rehabilitation took place on the training ground but he has made two substitute appearances in the last nine days and is now primed to take the place of Lampard and pull Chelsea's strings in midfield.

The England man has been sidelined with another torn thigh muscle, this time in his right leg, and while the club said he will be out for "a few weeks" the last thigh problem took more than a month to get over earlier this season.

Ballack didn't live up to expectations last term but he looked in good shape in Chelsea's Boxing Day draw with Aston Villa and scored with an impressive free-kick.

His return could not have come at a more important time for Chelsea as they are facing a crisis in central midfield next month.

Grant said: "I was pleased to welcome Michael back - he has had a difficult few months.

"He is a good and an intelligent player and I like them. I think he will contribute to the team."

Grant is reviewing his approach to the transfer window in the light of his new problems and may target Hamburg's Rafael van der Vaart to reinforce his midfield.

The Dutchman is highly rated by development director Frank Arnesen and has been talking about a move away from Germany.

Lampard's injury, sustained against Villa, deprives Chelsea of one reliable goalscorer and Didier Drogba, their other one, is also out injured and due to go on international duty.

The central midfield crisis is looming because Claude Makelele will be out for several weeks after an ear operation and Michael Essien and John Obi Mikel are due at the African Nations Cup shortly.

That could leave just Ballack and Steve Sidwell if no new signings are made. This situation comes at a time when the fixtures are piling up, with the Carling Cup semi-final to be played against Everton next month and key Premier League games including an encounter with Tottenham.

Tomorrow, Chelsea will get a taste of things to come when they face Newcastle at Stamford Bridge with Essien suspended and Lampard missing.

At the back they are stretched too with John Terry injured, Ricardo Carvalho suspended and Ashley Cole banned if his appeal fails.