Lindh Gallagher v Tig (see notes)

Notes

Use 1-set bookie that doesn't void retirements.
Here a list of bookies: https://www.rebelbetting.com/faq/tennis-rules
You should double check if the list is correct for the used bookie.

Tig might retire after first set or so...

If you can't back at a 1-set bookie, then alternative would be 7 units on the 1st set winner and 3 units on money-line winer at void bookie. I would also expect unibet to make it live-betting.