Arsenal take on Tottenham on Sunday
With the North London derby coming up on Sunday, maintaining discipline and avoiding red cards will be paramount for Arsenal and Tottenham players.
It's certainly on the mind of Arsene Wenger as the Arsenal manager looks ahead to a game that could reinforce his team's Premier League title credentials and hit Spurs with a further blow after the latter's midweek Champions League defeat to Bayer Leverkusen.
Wenger is particularly concerned by the disciplinary record of midfielder Granit Xhaka, who already has a red card to his name this season after being given his marching orders against Swansea in a 3-2 win.
The midfielder was on the receiving end of three red cards in the Bundesliga last season for former club Borussia Monchengladbach.
With that in mind, Wenger is hoping the Swiss international keeps his cool and Arsenal's overall discipline in the cauldron of a derby environment.
"I'm a bit concerned yes because the discipline is important. We want to be effective in all positions we face. In derbies it is important to maintain discipline," he said, before discussing Xhaka.
"He's quite normally a composed and calm guy - sometimes he has a reaction that is a bit impulsive. He has to work on that and keep control of his reactions in the game."
Arsenal are joint-top with Manchester City and Liverpool on 23 points, while Tottenham are fifth but just three points behind in a tight battle at the top which also involves in-form London rivals Chelsea at this stage of the campaign, with 10 fixtures played.
The last two league derbies between Arsenal and Spurs have finished in draws, with a 1-1 result in November 2015 at the Emirates followed by a 2-2 draw at White Hart Lane in March.
Arsenal's Francis Coquelin received a second yellow card and was sent off in the latter fixture, although Alexis Sanchez's equaliser meant Arsenal avoided defeat.