in Italy during the late 1980s, where he completely revitalised the movement supporting this formation. It was also the formation with which Norwegian manager Nils Arne Eggen won 15 Norwegian league titles. Most teams using this formation now use the specialist defensive midfielder. Recent famous examples include the Porto and Chelsea teams coached by José Mourinho, as well as the Barcelona team under Pep Guardiola. Mourinho has also been credited with bringing this formation to England in his first stint with Chelsea, and it is commonly used by Guardiola's Manchester City. Liverpool manager Jürgen Klopp is a proponent of the technique, using it to lead the team to victory at the 2018–19 UEFA Champions League final, as well as lifting the 2019–20 Premier League title. 4–3–1–2 A variation of the 4–3–3 wherein a striker gives way to a central attacking midfielder. The formation focuses on the attacking midfielder moving play through the centre with the strikers on either side. It is a much narrower setup in comparison to the 4–3–3 and is usually dependent on the "1" to create chances. Examples of sides which won trophies using this formation were the 2002–03 UEFA Cup and 2003–04 UEFA Champions League winners Porto under José Mourinho's; and the 2002–03 UEFA Champions League and 2003–04 Serie A-winning Milan team, and 2009–10 Premier League winners Chelsea, both managed by Carlo Ancelotti. This formation was also adopted by Massimiliano Allegri for the 2010–11 Serie A title-winning season for Milan. It was also the favoured formation of Maurizio Sarri during his time at Empoli between 2012 and 2015, during which time they won promotion to Serie A and subsequently avoided relegation, finishing 15th in the 2014–15 Serie A season. 4–1–2–3 A variation of the 4–3–3 with a defensive midfielder, two central midfielders and a fluid front three. 4–3–2–1 (the "Christmas tree" formation) The , commonly described as the "Christmas tree" formation, has another forward brought on for a midfielder to play "in the hole", so leaving two forwards slightly behind the most forward striker. Terry Venables and Christian Gross used this formation during their time in charge of Tottenham Hotspur. Since then, the formation has lost its popularity in England. It is, however, most known for being the formation Carlo Ancelotti used on-and-off during his time as a coach with Milan to lead his team to win the 2007 UEFA Champions League title. In this approach,