What is the on-field role of the captain?

Question

After watching the John Terry "stripped of captaincy" episode in the England national football team, my question is what exactly does the captain do on the field?

The team tactics are decided by the manager, and the managers do pass on instructions during the game via the closest available player to the touchline/dugout.

What does the captain do on the field?

I assume off the field they can be providing strategic inputs and mentoring youngsters and so on

Answer 1

The FIFA Rules of the Game published for the 2011-2012 season make the following rules applicable for the captain;

1. The referee tosses a coin and the team whose captain wins the toss decides whether to take the fi rst or the second kick
2. [In the event of a penalty shootout...] If one team has a greater number of players than its opponents, it must reduce its numbers to equate with that of its opponents and the team captain must inform the referee of the name and number of each player excluded. Any player thus excluded may not participate in kicks from the penalty mark.
3. [On the subject of dissent...] The captain of a team has no special status or privileges under the Laws of the Game but he has a degree of responsibility for the behaviour of his team.

However, outside of the laws, it is often expected the captain has the responsibility of...

1. Motivating his fellow players (although I'm not sure how important this is; I'm unsure how a captain that is a goalkeeper can motivate his players.)
2. Keeping a cool head. Calming down fellow players when things get a little heated (obviously this is something all players can do, but it's something you expect the captain to lead).
3. Furthermore (and perhaps most importantly in the current day) they act as a medium between fellow players and the officials. Gone (or going) are the days where an entire team of players surround the officials to try influence a decision. Instead you tend to see the (outfield) captain making his point of view heard to the referee. Similarly, you often see the captain being a medium between a referee and a player in the event a player gets pulled up... ensuring the player keeps a cool head and a fair conversation takes place (from his point of view :P).

Off the field their most important role is that they are one of the most recognised people of the team; the manager, then the captain. They are the leaders of the team, and (rightly or wrongly) the teams public image can be strongly affected based on the image and actions of these people. The other players in the squad inevitably fall behind these two people. Of course, all members of the squad are public facing, and should act as such, but this is even more so for the captain.

Being specific to the John Terry incident, the worst scenario the FA could have is the captain of the England Football team being criminally charged with racism. Sure, a squad member being criminally charged hurts, but eventually it gets brushed under the carpet... there's 22 other squad members to think about. It is not that easy to forget about the single captain and single manager, however.

Answer 2

In addition to the FIFA Laws of the Game rules that Matt outlines in his excellent answer, continental and national associations may have slightly different or supplementary rules for captains, although national associations tend to be in line with the continental association they belong to. In any case, captains are expected to be exemplars of on field behaviour.

The most recent regulations for UEFA are the Regulations of the UEFA European Football Championship 2010-2012, and what applies to captains is:

14.04 Before each competition match, each team receives a match sheet on which the numbers, full names, dates of birth and, if applicable, the shirt names of the 18 players in the squad (23 players in the final tournament) must be entered, together with the full names of the officials seated on the substitutes’ bench and on the additional technical seats. The match sheet must be properly completed in block capitals and signed by the captain and the head of delegation.

...

16.04 If the taking of kicks from the penalty mark cannot be completed because of weather conditions or for other reasons beyond control, the results will be decided by the drawing of lots by the referee in the presence of the UEFA match delegate and the two team captains.

...

23.02 Protests concerning the state of the field of play must be submitted to the referee in writing by the relevant officials before the match. If the state of the field of play becomes questionable in the course of the match, the team captain must inform the referee, in the presence of the captain of the opposing team, orally without delay.

In some national associations, if a player is cautioned or sent off and a suspension applies, the period of suspension is doubled if the player was captain at the time of the offence. Although I can't find a reliable reference for, I think that the doubling of the suspension time applies even if a player was acting captain at the time, receiving the armband after the regular captain went off field due to injury or substitution.

At club level, captains have various roles that can range from traditional to official:

1. They lead negotiations with club owners and managers regarding internal regulations, bonuses, etc, and in some associations such regulations are only valid if signed by all captains,
2. They are generally expected to act as the public face of the players, it's not uncommon to see captains taking full responsibility after a loss,
3. They are generally expected to act as mentors to younger players, especially players in youth and reserve teams.

Answer 3

They usually participate in huddles with the refs for stuff like the coin toss to decide initial possession and stuff like that - and are generally regarded as one of the better players/leaders of the team. Other than that I suspect it's just a glorified title.