The half-backs and the full-back, who is practically a third half-back, stand usually from two to four yards behind the center of the line. They group themselves at short distances from one another and in a way to best assist in carrying out the play which is about to be made. There is a difference in the latitude given the half-backs and full-back on different teams in arranging themselves for each play. Some captains require these men to occupy the same position on every play, claiming that it is of great advantage in obscuring the play to have a fixed arrangement. On other teams the half-backs and full-back are allowed to move about, and shift their places to the position in which they think they can best help out the play.

There is also a great difference among teams in the placing of the half-backs and full-back in reference to each other and also in reference to the rush line. In general, the full-back is stationed behind the center and usually about a yard or a yard and a half further from the line than the half-backs. On some teams, these three play close together, separated by not more than a yard or a yard and a half; on others, they are separated from two yards to three yards and a half. There is also a decided difference in the distance behind the line which the backs play. This varies from two to five yards.

The arrangement of the backs should, in a measure, depend on the style of game to be played; and the style of game should be determined by the composition of the team. That is to say, that if it is deemed wise to play a center game, it can best be done by bunching the backs; while, on the other hand, the combinations can be best made for an end game when the backs are more spread apart.

Captains who are limited in the selection of their players will find it well worth their while to consider the arrangement of the backs, both in regard to their relative distance from each other, and also in regard to the distance which they stand behind the line. Indeed, there is an opportunity for fine generalship in deciding upon the place for these ground gainers.

When the three men who are to occupy positions behind the line have been decided upon, there is also need of careful consideration in determining which position each one of the three shall fill. The full-back is usually selected for his ability to kick, and yet, it is sometimes better that the man occupying that position should act as a half-back until the signal for a kick is given, and then drop back; while a half-back sometimes could do more effective work in the middle position during the general play. If one of the backs is slow, his best position is usually at full-back, for there he receives the greatest protection and help. The light, quick men can succeed better at half-back than the slow, heavy men.

It frequently happens that one of the backs invariably carries the ball under the right arm and is able to use only the left effectively in blocking off, or vice versa. This fact should be considered in determining which position the men shall occupy.

It is unfortunate for a half-back to be so limited, but many of them are, and they do not practice with the other arm enough to train it. Some naturally run in one direction better than in another; or some are surer and stronger of foot, perhaps, when running around on a particular side. A player is sometimes put in the right or left position because the interference is stronger on that side; or possibly the arrangement is made to take advantage of a certain known strength or weakness in the team which they are to meet.

The half-backs and full-backs are largely the ground gainers for the team and most of the advances into the enemy's territory are made by them. For this reason, only men who possess special qualifications are selected to fill these positions. In quickness and agility they should equal the quarter-back; in point of speed, ability to dodge, courage, and dash, they should be unequaled by any man on the team. Again and again they must rush headlong into the line, oftentimes only to be hurled back by the opposing rushers who plunge through upon them. Yet, never losing courage, again and again they must come to the rally, now attacking the opponent's center by heavy plunging now trying to make a detour around the wings.

Too great emphasis can not be placed on quick starting. The inability to get under headway quickly is very often the difference between a first-rate half-back and a second-rate one. The second-rate half-back may be just as fast a runner, and may be just as hard to stop when once under way, but he does not get under headway nearly so often, because he loses so much time on his start that he is tackled before he passes the critical point in the run. On all plunges into the line the utmost speed must be used in conjunction with the quick start. The distance is very short in which to get under headway, and there is need of the greatest force to project the runner through the resistance, as well as need to reach that point of resistance in the shortest time. It is common with many elevens to have one heavy back to do the plunging into the line, but frequently this man is so slow in his start that he is not so effective for line-breaking, against a strong defense, as the lighter man would be. It very frequently happens that in choosing the half-backs, men have to be selected who have only part of the qualifications for the position; who perhaps can run fast, or, again, are what are termed "fighters," but lack some of the other requisites When such is the case, the captain should immediately take means to train these men in the other necessary qualifications for good half-back play. It is indispensable that a half-back should be able to run into a line hard time and again, and with no fear or hesitation. It is likewise most necessary that a half-back should be a powerful runner and not easily stopped; one who does not fall easily but keeps his feet well when tackled, and struggles on for the gain of a few feet. But he would be a much more useful man if, at the same time with this pluck, determination, and ability to stand on his feet under difficulties, and keep struggling forward, he also had the ability to dodge an opponent or ward him off with the extended arm, instead of running straight into him.