It don't lok like it . But from your description. It sounds like Johnson grass.
So id treat it as so ! Sounds like same qualities ! thats (dis-) 😬 plow it under. Each section of plant and each section of root will grow anew ! 😡 ya gotta dig it out. And as soon as it starts comin back very small dig it out again.so on an so on. Dats only way to get rid of it permataly !
Sorry 😫 Ya might say "roundup" well....
That will take many yrs. If ever. Ive been battling nutgrass 20+yrs and purslane also. To no avail. But i heard from another nga member to use boilin water . There post is somwhere on garden.org
😎😎😎"The cool gardener"