Setting a loop point inside an animation?

I have a dash animation which plays with a brief introductory transition, then loops the dashing state indefinitely. What I’d like to do is play the transition once and then loop the dashing portion of the anim.

I know this can be done easily with montages, but the problem is I want to use the dashing animation inside a blendspace, so I can add leaning when the player turns while dashing. Obviously blend spaces can’t be played from within montages, so I need some other way to tell the dash animation where to loop back on itself.

Is there a way to do this? Or will I have to rig up some sort of transition state in my anim graph to handle the initial movement to the dashing state?