Can't enter horse in claimer

Racing
1

I’m trying to enter Valint Effort in a claimer as I realised I don’t have the patience to fathom him, but he doesn’t . I thought Claimers could count as the third race on a horse’s ‘to sell’ number

Clarification please

2

I don’t think they can, I’m pretty sure it expects you to race them 3 times and then they’re eligible for claimers.