Kerber won their only previous meeting. That was in March this year. She won when Bertens retired in the third set.
Kerber loses focus after she wins a title. It happened after she won the Australian Open In January and has happened again more recently. She won in the title Stuttgart but has lost her 2 matches since then. Her worst finish at the French Open in the last 4 seasons was last year’s third round.
Bertens won a title in Nurnberg last week as a qualifier She may be feeling the effects of playing 7 matches that week. I see this going to 3 sets.
Value is on Bertens at the startbut unless Kerber is very poor I think the German will be physically stronger.
Back Kerber if she goes a break behind. Lay the set 1 winner