Manchester City boss Pep Guardiola is said to have targeted Lisandro Martinez against Manchester United.
The Argentine central defender had put aside a poor start to the season by putting in several impressive displays for the Red Devils.
However, he and his teammates were undone against City and Erling Haaland last weekend, going 4-0 down at half-time and losing the game 6-3 in the Premier League.
Per ESPN, Guardiola did not want City to focus on Martinez's height, which has come in for some scrutiny.
Instead, he wanted forward Haaland to occupy the Argentine, which would leave space in behind for attacking midfielder Phil Foden to run into.
The tactic worked, with Martinez going up to mark Haaland, leaving Foden to expose the left side of United's defense.