Having looked up the prasal verb "to check up" in all available dictionaries I have found its being used in the sense of "to make certain about something by checking it, verify or to comport with" mainly with an object (direct: check the figures up or prepositional: check up with the data, check up on smb/smth).
But there were a pair of examples of the verb in which, as I may be guessing, it meant something like "to stop": "They had such headway that they were nearly to the king before they could check up; then, frantic with rage, they stood up their horses on their hind hoofs and...(after Mark Twain, A Connecticut Yankee in King Arthur's Court).
Is "to check up" used in the meaning of "to stop" or I just got it wrong?
And are there any other rare senses in which this phrasal verb may be found used whithout an object (as an intransitive verb)? (I, for example, couldn't figure out its meaning herein: "Also, if the ball goes out of bounds players must check up").