David Luiz was sold to Arsenal because he ignored Frank Lampard's tactics in a preseason friendly.
Chelsea parted with the 32-year-old centre-back for a measly 8m on deadline day.
It has been revealed by The Athletic that Lampard was dismayed with the Brazilian's performance against RB Salzburg.
Lampard was reportedly shocked by the amount of long balls Luiz attempted, going against his tactics.
He was subsequently dropped for the following friendly against Borussia Monchengladbach.
