In most plays the part which each player shall take in the interference can be laid out very definitely, but in the end play, and plays between end and tackle, only part of the interferers are to take particular men; the rest block off whatever opponents come in their path. It is in this free running that there are frequent chances for the display of fine team play in interference in striking the opponent at the nick of time, in pocketing him, in forcing him in or out as it seems best on the instant (the runner being on the watch for either), and in the runner sometimes slowing up to let an interferer who is close behind go ahead to take the man. Very often the reason that a play is not successful is because the interferer is too far in advance of the runner to be of any service to him. Interference must be timely to be effective. It must be the projecting of a helper at the moment a point of difficulty arises the swinging into line of a series of helpers in timely sequence as the runner advances. Nor must the runner be delayed by the interferers except, perhaps, when the guard comes around on an end play where it is necessary to slow up a little at a certain point to let the guard in ahead.

The execution of nearly all the plays depends for its success on each player doing his duty at the right moment. Here and there in certain parts of the play one or more players must delay a particular work as much as possible, otherwise their action would be immature and so valueless; but for the most part, the movement of each player should be quick and definite, and those plays are most effectively made in which every player does his duty quickly.

Naturally, the end plays and the plays between end and tackle require more delicate adjustment of the players in the interference than do the center plays. In the latter, the interference nearly always must be done after the line has been reached and penetrated. Here the extra men, who rush to the opening as soon as they see where it is, will be encountered, while in the end runs an opponent is likely to show himself here and there and everywhere before the runner reaches the line.

In all mass and wedge plays where the pressure is brought to bear on one point in the line, the team play is not nearly so delicate and skillful. The virtue in the wedge play, be it quick or slow, lies in the power to project great weight and strength on a given point, while at the same time closely protecting the runner.

Every play should be made as safe as possible by having at least one player always in a position to get a fumbled ball, or in case an opponent secured the ball, to prevent him from making a run. Where there are so many parts to every play in snapping, handling, passing, and catching the ball, there is constant danger of a slip. The value of having one or more players behind the runner is frequently demonstrated also, when, by the aid of a timely push, the runner is able to break loose from the grasp of some tackier who has not secured a strong hold on him, and so adds several yards to his run.

In running down the field on a kick the rushers should run in parallel lines two or three yards apart, for most of the distance, converging as they approach the man with the ball, in order to pocket him. The ends approach the catcher in such a way that he will be forced to run in towards the approaching rushers, if he runs at all. All must be on the watch to thwart a pass to another man.

There is a nice point in judgment to be considered by the rushers in going down on a kick. The end men being so far away from where the full-back will stand when about to kick, can start instantly down the field, leaving the half-backs to block off their men if they come through too fast; for the ends' first duty is to be under the ball when it falls. Occasionally, when kicking from near the side line, it may be necessary for the end next the side line to block his man or to push him back as he breaks through to go down the field. What the ends will do in this case, the tacklers should do nearly every time that a kick is made. Both tacklers should feel it their bounden duty to support the ends by going hard after them the instant they judge their opponents cannot reach the full-back in time to interfere with his kick. Hence, any tactics which they can put into practice which will enable them to block their opponents and, at the same time, not delay them in going down the field are the ones to be used. The tackles must bear in mind that the distance from their positions to the fullback is not very great, especially on the side on which the full-back kicks; but while this makes the duty of blocking on that side greater, the other tackle can afford to take an extra fraction of a second from blocking his opponent and use it in a quicker start.

On the guards and center rests the greatest burden in blocking their opponents on a kick; for while there is not that openness in the line, as at the tackle and end, which will let an opponent through quickly, the distance to the full-back is here the shortest and it is usually here that tricks are worked by which one or two men are let through, one usually being the quarter-back. They must, therefore, be very careful not to be over hurried in going down the field, remembering that it is their first duty to block, following the tackles and ends as soon as possible. If the guards and center are very skillful there need be no great delay in doing this, for it is necessary to check their opponents only long enough to enable the full-back to punt over their heads. Whenever it is possible for the guards and center to carry their men before them for a few feet, it is generally safe to leave them and go down the field at full speed It is comparatively easy for the center to do this at the instant that he snaps the ball. Generally there is too much blocking done and too little " following the ball."

In this connection, as a help to the rushers, several points must be borne in mind by the full-back in kicking. It is not enough for him to kick the ball as hard as he can each time it is sent back for that purpose. That would be a poor performance of his duties. He must kick for his team's advantage always, and therefore must regulate the distance, and direct his kick with the utmost skill. Even long and puzzling kicks are dangerous unless closely followed up by the rushers; for, let a good dodging half-back get free, with one or two interferers in a broken field of opponents, and he will be almost sure of a long run.

The full-back must take into account the ability of the rushers to get down the field in time to prevent a run or a return kick and punt accordingly. He may find it necessary to elevate the angle of his kick so that it will give his men time to get under it, or he may find it best to direct the ball straight ahead, in order to give his rushers the shortest distance to run, and at the same time be able to advance in the best formation for checking a run. At least, he must punt the ball where it shall be difficult for the backs to reach it quickly, and so give the rushers the advantage of a longer time to get under it. Especially must he be very careful not to kick the ball diagonally across the field without weighing well the risk involved, in comparison with the chances for increased advantage; for the risks are unusually large in such a kick. It would be well for the full-back to give the rushers a signal as to the direction he meant to kick. This should always be done when he intends to kick off to one side of the field, or when he purposes making a high kick or one outside of bound in order to put his men on side by running forward. The rushers would be able to work some splendid team-play on such occasions.

The question of when to make a fair catch and when to run is well worth the consideration of the backs, who are the ones almost always called upon to exercise their judgment on this point. It was formerly judged best, in handling a kicked ball, to make a fair catch on all occasions. To-day there is a division of opinion, some adhering to the old way, while others prefer to run whenever they get a chance.

There are two points to be considered in deciding this question: First, whether it is possible to kick a goal from the place where the ball will fall, or whether a punt from that point would be desirable; second, whether it will add much to the risk of not catching the ball, if the attempt is made to run. It is clear, that when near enough to the opponent's goal to try a place kick, every effort should be made to secure a fair catch.

When a goal from the field would be impossible, it is almost invariably best to run with the ball, unless this would add greatly to the danger of muffing it. Catching the ball necessitates a positive loss of ground before again putting it in play, and it is doubtful whether this loss is compensated by the advantage of putting it in play unmolested by opponents and behind the whole team under slight headway.

In attempting to run the player will at the worst be forced to make a down, which would furnish only slightly less advantage than a fair catch, while on the other hand it presents opportunities for gain.