A midfielder is an association football position. Some midfielders play a more defensive role, while others blur the boundaries between midfielders and forwards. The number of midfielders a team uses during a match may vary, depending on the team's formation and each individual player's role. The group of midfielders in a team is called the midfield.
More complete midfielders require a number of skills on top of fitness: they tackle, dribble, shoot and pass during any match. Most managers field at least one central midfielder with a marked task of breaking up opposition's attacks while the rest are more adept to creating goals or have equal responsibilities between attack and defence. At either side of the pitch a manager can field a right or left midfielder, who are used equally for both attack and defence, or a winger, a player used primarily for attack.
In essence, a good midfield must possess the ability to be combative while also being creative. A good striker without midfield support could lack attacking chances, while a defense likewise could be severely tested. Because they occupy the most influential parts of the pitch, midfielders are perhaps more likely to influence the outcome of a match than other positions, especially if they have vision for a good pass or ability to score.
Midfielders typically expend the most energy during a match because of the distance they cover on a pitch, as at times they can be called back into defence, or required to attack with the strikers.