Costa was at the heart of a fiery reverse fixture at Stamford Bridge earlier in the season, with the Spaniard goading Arsenal centre-back Gabriel into kicking out at him and getting sent off, before subsequently picking up a three-match ban of his own.
On that occasion the Gunners lost 2-0, with Santi Cazorla also seeing red, and Wenger has called on the referee, Mark Clattenburg, to keep things under control, while also warning his players to not lose focus, per John Cross in the Mirror:
We have to be prepared for a battle because Costa gives you a fight. After that, it's down to the referee. We have to focus on our performance. It's another game where people look at us and see how we behave. It will be an intense game—as usual in the Premier League. Overall, I think because of the qualities of the players on the pitch and what is at stake for both teams, it will be a very intense battle.
The Gunners must be classed as favourites for the north London clash—they are top of the league and Chelsea are in 14th.
However, Arsenal have a poor recent record against the Blues and have not beaten them in the league since 2011.
Equally, while Chelsea have hardly shot up the table since Guus Hiddink was appointed as manager, they have yet to lose under the Dutch manager and will likely set up to frustrate the Gunners.
Bleacher Report's Dean Jones recently named Arsenal as the favourites for the Premier League title this season following their battling 0-0 draw with Stoke City last time out:
Wenger's side should be boosted by the return of two vital players, with Mesut Ozil and Alexis Sanchez set to be included in the squad, per the ESPN FC's Ben Dinnery:
And there is no question that Arsenal have been better than Chelsea this season.
They have lost only once in the league at the Emirates—while the Blues have won just two from 10 on the road—and given the two sides' disparate league positions, it should be an easy win for the hosts.
But the Blues seem to have a knack for beating Arsenal, and Costa himself is very adept at getting under the opposition players' skins.
The hosts need to keep their cool at the Emirates if they want to pull off a potentially vital win against the defending Premier League champions.