I see the problem!
"I have landed on Phobos and am being attacked by a Z-class cruiser. Think I can hold out until you come, but hurry."
Then K.15's ship stopped blasting. It had obviously exhausted its fuel, and was doing a little better than six kilometers a second away from the sun. K.15 must have landed, for his ship was now speeding helplessly out of the solar system. Commander Smith didn't like the message it was broadcasting, and guessed that it was running into the track of an approaching warship at some indefinite distance, but there was nothing to be done about that. The Doradus began to move toward Phobos, anxious to waste no time.
On the face of it, Commander Smith seemed the master of the situation. His ship was armed with a dozen heavy guided missiles and two turrets of electro-magnetic guns. Against him was one man in a space-suit, trapped on a moon only twenty kilometers across. It was not until Commander Smith had his first good look at Phobos, from a distance of less than a hundred kilometers, that he began to realize that, after all, K. 15 might have a few cards up his sleeve.
Arthur C. Clarke: "Hide and Seek" (1949)