German tennis great Boris Becker “acted dishonestly” by failing to hand over assets including his Wimbledon singles trophies before and after he was declared bankrupt in 2017, a London court heard on Monday.

The 54-year-old six-time grand slam winner, who attended the opening day of his trial at Southwark Crown Court, faces 24 counts under the Insolvency Act relating to the period from May to October 2017. Becker, a former world No.1 who won Wimbledon three times, denied the charges. The trial is expected to last three weeks.

British media quoted prosecutor Rebecca Chalkley as saying Becker “acted dishonestly with regards to a number of his assets.

The charges include nine counts of not handing over trophies and awards and seven of concealing property valued at more than 1.5 million euros ($1.65 million).