Head to heads are at 2-2. They last met in March this year in Indian Wells. Bacsinszky won on a hard court in a third set tie break.
They have played twice on clay Both those matches were in 2016 and Bertens won them in straight sets.
Over all stats this season favour Bacsinszky. On clay they are more even though Bertens has played more matches. In the last 12 months their results on clay are very similar but Bertens beat better opponents
Anything can happen here but on clay I give Bertens the edge. 3 sets.
Update: Bertens won in straight sets.