A German banker who alleges he was bribed by Bernie Ecclestone testified for the first time Friday in the Formula One boss' corruption trial.
Gerhard Gribkowsky is the prosecution's star witness against Ecclestone, who claims he was blackmailed into making a $44 million payment to the banker.
Gribkowsky was sentenced to eight and a half years in prison in 2012 for taking the money after a trial in which the 83-year-old Ecclestone testified against him.
Ecclestone could face up to 10 years in prison if convicted of bribery and incitement to breach of trust.
Prosecutors allege the payment was meant to facilitate the sale of Munich-based bank Bayern LB's 47 percent stake in F1 to a buyer of Ecclestone's liking.
The Munich court has set aside four days for Gribkowsky's testimony.