Moving to Chelsea, in the 2009–10 season Ancelotti continued with 4–4–2 diamond formation used previously at Milan, often with Michael Essien or Mikel John Obi in the defensive role, Michael Ballack or Frank Lampard as box to box midfielders and Deco in a creative role, with full backs Ashley Cole and Jose Bosingwa pushing forward and providing width to the narrow midfield. Later in the season the Africa Cup of Nations left Chelsea without strikers Solomon Kalou or Didier Drogba (as well as midfielders Essien and Mikel) and harder to play 4–4–2, so Ancelotti switched to the 4–3–2–1 "Christmas Tree" formation he had used at Milan, using Joe Cole and Florent Malouda to support lone striker Nicolas Anelka. He also used 4–2–3–1 and 4–3–3 to be less predictable and better use creative players like Lampard and Malouda.