Costa has proved a thorn in the side of Arsenal's defence in recent times, including scoring the winner in the meeting between the two teams at the Emirates Stadium last season.
The London clubs renew their rivalry on Saturday with Arsenal looking for a first Premier League win over the Blues since October 2011.
Costa will lead the line for Chelsea having been involved in two flashpoints when the clubs met last year - firstly Gabriel was sent off at Stamford Bridge after tangling with the Spain forward before Per Mertesacker saw red for hauling him down in the game at the Emirates.
Constantly niggling and riling his opponents as become part of Costa's game, with the 27-year-old lucky to escape to red cards already this season.
And, while Wenger admits he is an admirer of Costa, he feels he can be just as good if he removes the fiery aspect of his character.
"I like him as a player
I like the qualities of the player but all the rest around is not needed," the Arsenal boss said. "He is a fighter and you respect that
The rest is down to the referees to get the game and the rules respected.
"He's a very strong player
He looks since the start of the season to have cleaned up his act, that he behaves more focused on the game
And that makes him more dangerous."
Wenger, who said Costa was on his radar but he was caught out when the striker opted to leave Atletico Madrid for Stamford Bridge in 2014, has told his defence to remove the emotion from coming up against him this weekend.
Asked how his defence can face up against Costa, Wenger replied: "By being completely cold-blooded and just focus on the game and not respond
Just try to negate his qualities and his game.
"You need to be committed but by respecting the rules of the game and responding
Last year we were a bit unlucky at Chelsea to be down to 10 men because we got a red card and it was rescinded after.
"In the other game, we deserved the red card because we were caught on a quality run by him."
Wenger admits he has also discussed discipline with his players following their recent run of cards against Chelsea.
"We talk about that because in the last two games, we've played against Chelsea with 10 men" he said.
"Of course for the result tomorrow it will be important the way we play football, but as well the way we behave, because discipline and results are strongly linked and the results we've had in the last two games are that we couldn't play 11 against 11."
The Gunners will be without Aaron Ramsey for the game after Wenger confirmed the Wales midfielder is still missing with a hamstring problem which is likely to keep him out of the next round of international fixtures.
Olivier Giroud faces a late fitness test as he looks to overcome a toe injury to be involved, while Wenger is expected to make wholesale changes having named a completely different starting XI for Tuesday's EFL Cup win at Nottingham Forest.
Source : PA
Source: PA