Kamui Kobayashi will deputise for Timo Glock at Toyota in the Brazilian Grand Prix after it was revealed that Glock sustained a cracked vertebrae in his Suzuka accident.
The German missed last weekend's Japanese GP having crashed heavily at the exit of the chicane in qualifying. It was initially thought that his injuries were limited to a cut leg, which restricted his mobility enough to rule him out of the Suzuka race but was not expected to cause any further problems.
But today Toyota announced that further medical checks in Germany have revealed the injury to his back as well. This will prevent Glock from racing in Brazil, and team boss John Howett admitted that he was also in doubt for the season closing Abu Dhabi GP a fortnight later.
"Obviously everyone in the team is very disappointed and feels for Timo," said Howett. "We wish him a very speedy recovery. Based on the initial diagnosis, we fully expected Timo to return in Brazil but unfortunately a different injury has been revealed which prevents that.
"He will remain in Germany to recover and we hope he can recuperate in time for Abu Dhabi, although at this stage the situation is not clear."
Toyota reserve driver Kobayashi had deputised for Glock when an illness prevented him from running in Friday practice at Suzuka. His Interlagos appearance will mark the GP2 Asia champion's grand prix debut.
"Kamui was the natural choice to step in and he proved in Suzuka that he is capable of holding his own," said Howett.
"It is a difficult task for him but he knows the team will give him its complete support and we know he is motivated to make the most of this unexpected opportunity."