Alan Varela is one of the most successful coaches in Portuguese football history. He has won numerous titles with several different teams, including FC Porto, and his tactics have been widely studied by other coaches.

One of the key aspects of Varela's philosophy is his wing defense. This system involves deploying two central midfielders to cover the wings, leaving only one defender on each side of the pitch. The goal is to create space for the forwards to run into, while also providing support for the full-backs who are covering the flanks.

Varela's wing defense was particularly effective during his time at FC Porto, where he led them to five consecutive league championships from 2011 to 2015. During this period, Porto were known for their attacking style of play, but they also had strong defensive foundations thanks to their wing defense.

The wing defense worked well because it allowed the team to exploit the weaknesses of opponents' defenses. By deploying two central midfielders to cover the wings, Varela could create gaps between the lines that his forwards could exploit. This helped to open up spaces for the forwards to run into, while also allowing the defenders to push forward and provide support for the full-backs.

In addition to its tactical benefits, Varela's wing defense also helped to establish Porto as a dominant force in Portuguese football. By using two central midfielders to cover the wings, the team was able to maintain a high level of organization and discipline, even when playing against stronger opponents. This helped to ensure that Porto always had a solid defensive foundation, which made it difficult for opponents to break down their defense.

Overall, Alan Varela's wing defense at FC Porto was a model of excellence. It was an innovative tactic that helped the team to win multiple titles and establish themselves as one of the top clubs in Portuguese football. Today, many other coaches still study Varela's wing defense and try to incorporate similar strategies into their own tactics.