Transplant shock. It will recover. Planting in midsummer during record breaking temps is bound to create issues.

Rather than a watering can, I'd try watering with a hose on a slow trickle left in place for a suitable length of time to make sure all the soil surrounding the rootball - and the rootball itself - is adequately hydrated. And check for some surface drying before watering again.

agree ... and if you deep water like that ... you PROBABLY need to do it once a week or so .. since the moisture at depth isnt going to evaporate all that fast ..

keep in mind.. we need water at root depth.. and the surface is rather irrelevant ...

if it survives.. and it will if you get proper watering ... increase the ring of soil to at least 2 feet... and add mulch ...

ken

good primer here: https://sites.google.com/site/tnarboretum/Home/planting-a-tree-or-shrub