'You can't afford to concede set-pieces'
The importance of set-pieces in football is the driving force behind Per Mertesacker's excellent disciplinary record.
The Arsenal defender has received just one yellow card in 16 appearances for his new club and had an even better record at Werder Bremen with a solitary booking in his last 67 Bundesliga games.
That impressive record is no accident, according to the Germany international.
"Set-pieces are very dangerous in the modern game," Mertesacker told Arsenal Player.
"They can make the difference in the game and therefore you have to defend your goal the best way you can, and that's my way. You have to be patient.
"You are always looking for the ball, that is the main thing for me. You want to win it and that's the main reason [for my record]."