Lacazette scored the winning goal with ten minutes remaining against Neil Warnock’s side, smashing the ball into the top corner from a difficult angle.
Shkodran Mustafi and Pierre-Emerick Aubameyang had put Arsenal FC into the lead twice beforehand, but Cardiff equalised on both occasions thanks to goals from Victor Camarasa and Danny Ward.
Torreira was introduced to the action after 70 minutes and he made a huge impact on proceedings with his dynamic style of play and impressive technical ability.
After the match, Emery firstly praised Lacazette for his performance when speaking to Sky Sports.
“I’m very pleased. I spoke with him because I know him at Lyon.” he said, alluding to the French striker.
“I know he has a big capacity to score in the box and when the team gives him good options. He has good data to score and today he showed us. It’s good for his confidence.”
He then went on to single out Torreira for his impressive cameo but also insisted that the Uruguayan midfielder still needs more minutes under his belt to improve, as he continued: “He’s improving. He is getting to know his team-mates.
“For me, all the minutes he is playing is important for his performance. He needs to continue working.
“But it’s very important for me to think about others players, Matteo has started well and Xhaka is very important. We need good players. Lucas is like that.”
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