When referee Andre Marriner finally blew his whistle and signalled towards the centre spot, confirming Calum Chambers’ close-range effort in Arsenal’s Carabao Cup win over Leeds last month had crossed the line, the defender made a beeline for the dugout. He was mobbed by team-mates when he got there. Substitutes Alexandre Lacazette and Aaron Ramsdale were first to reach him. Mikel Arteta joined the celebrations too. But the man Chambers was looking for was Arsenal’s set-piece coach Nicolas Jover. Moments earlier at the Emirates Stadium, when Chambers was preparing to replace Ben White, Jover had told him he was going to score with his first touch. “That’s why I went running over to him,” said a grinning Chambers afterwards. “It was a nice moment.” His goal, nodded over the line following an Emile Smith Rowe corner just 23 seconds after his introduction, was one of seven Arsenal have scored from set-pieces so far this season. Their total of six in the Premier League is the joint-hi...