Morton was back with the team Tuesday following a detour to Pittsburgh for an examination of the injury that had forced him out early from Sunday's game.
"The doctor looked at me and said, 'You can go.' From the diagnosis, it's not going to get any worse," Morton said. "It's a comfort issue. I'll throw off the mound [Wednesday] to make sure."
Morton kept his arm limber by playing flat-ground catch in Rangers Ballpark's outfield, but the key test will be his bullpen session.
"I need to see him get on the mound and make pitches. He wants to pitch -- who wouldn't, at this point of the season? We'll see where it goes," said Hurdle, whose primary backup option appears to be Brandon Cumpton.
While acknowledging this is an issue with which he has dealt before, Morton said, "I prefer not going into more detail."
He had felt "something abnormal" when running to cover home plate after uncorking a wild pitch in Sunday's game against the Cardinals.
John Buck, his catcher that day, had said Morton reported having "felt something pop."
"I'm sure a lot of guys deal with irritation in that area [the heel and sole of the foot]. This is a little different," Morton said. "It doesn't feel great. I just have to make do. The thing I have to watch for is not changing my throwing mechanics because of it."