Updated: Feb 16
The 2–3–5, originally known as the "Pyramid", was a long-term successful formation back in the 1880s. Believe it or not, it was pretty much the normal football formation in the UK, something like today's 4-4-2, 4-3-3 or 4-2-3-1, it was hugely popular. The 2-3-5 pyramid shape is actually not too strange. Recently, I covered Pep Guardiola's Manchester City 2020-21 tactic and he achieves a similar shape but in transitions and not as a starting position. He may start of using a more traditional 4-3-3 shape but as the play develops, the wing-backs come inside and form a line with the holding midfielder, this would leave 2 at the back and 3 holding midfielders. Two central midfielders could join the attack and this would effectively make a 2-3-5 shape.
The formation would usually consist of 2 defenders (side-backs) and 3 central midfielders (half-backs). The 2 central defenders would have the job of marking the attackers in their zone and the 3 central midfielders would cover the areas needed, that could be the flanks to engage tackling the wingers or the gaps possibly made in half-spaces and in between the lines.
The use of, essentially 5 defenders, and 5 attackers strikes a balance. But this also gives you the possibility of having a numerical advantage in central attacking areas as you will have 3 attacking occupying central areas. This is far from easy to defend because then the formation would have two wingers who stretch play, so if the opponent's full-backs choose to close down or mark the wingers, this leaves space for attackers to attack the channels (the space between the full-backs and central defenders).
In an attack, things can be easy to read if the attackers are assigned to the same duties/roles, which is why you'll usually see teams who use this shape in their transitions would have some variations in their attack. Instead of having all 3 central attackers running forward into channels, you have the option to use an attacker as the main creator. Asking him to drop deeper to collect the ball can disrupt any defensive shape because the opponents would have a choice to make, stay or follow. A defender may not want to follow in case it leaves space in-behind him but he also may not want to stay and allow your creator to create. This is where you can force your opponents into mistakes when making decisions and in moments like this, a game could be won.
In build-ups, the midfield 3 would be vital in ball progression. With the 5 attackers occupying the final 1/3 areas, the ball needs to work its way from defence to the attack and the midfield 3 need to be confident in doing so. For solidarity in the team shape, the midfield 3 wouldn't look to roam around the pitch for multiple reasons. They need to consistently be an option in deeper areas for the ball to progress unless you look to attack with a direct ball. Also, in case the ball is lost, the midfielders need to be in positions where they can stop a counter-attack and protect the back 2. Once the ball has worked its way forward to the attackers, they could be expected to use positional rotations. This is a way to create space and disorganise the opponent's defence by giving the attackers freedom. One idea could be when the ball is out to a wide player, one of the central attackers can look to move into the wide-area to create a 2v1 situation, the central attacker can then take control of the ball whilst the winger then takes up the position the central attacker was occupying.
Defending is where you can have issues when starting out with a 2-3-5 formation and I'm pretty sure everyone can spot the weakness, the flank areas. Having just two CBs leaves a massive space out wide for teams to attack which is why it would be essential to do most of your defending in central areas. You may want to force your opponent into the central areas as a trap in order to win the ball OR you can allow your opponents to have the flank area if you don't consider that a dangerous area to concede but either way, pressing would have to be done expertly to make sure players are not leaving their positions at times that would leave spaces for the opponents to then attack your defence directly. Starting off with a lower line of engagement or mid-block may be wise to force your opponents to play out a little. Having your attackers inviting pressure rather than closing down may give your team some solidarity and make the opponents think twice with the ball as they know one direct ball can beat all 5 attackers. But with the attackers dropping off and inviting the opponent's defence with the ball, you can then trap them in the middle of the park where you can potentially have 7/8 players ready to engage the opponents. So if it's pressing we want, the pressing can be done in the middle of the park where it's much safer.