Fortigate Proxy based on Path(Reverse Proxy)

I'm running a service, which up to today, I have consumed subdomains from my main domain for each customer to reach to their servers as below.

e.g:

  cust1.mydomain.com   --->  Proxy to customer1 
  cust2.mydomain.com   --->  Proxy to customer2

I did this via Fortigate 90D with a combination of web filters.

Now I'm looking for a better solution to stop consuming my subdomains for each customer and use mydomain.com as my main domain (as before) and proxy different customers based on URL to their servers.

e.g:

  mydomain.com/cust1   --->  Proxy to customer1 
  mydomain.com/cust2   --->  Proxy to customer2

is this possible to be done via Fortigate?