The Gunners were unfortunate not to be given a spot-kick when Jack O'Connell appeared to trip Nicolas Pepe in the second half:
Per the Mirror's Liam Prenderville, Arteta said:
"I think it's very clear. It was the same as with Chelsea, very clear. I don't know how many tools do we need?
"If you don't score the second goal, the game is always open.
"I can't remember any shots from them until they scored the goal. We completely controlled the game before then but couldn't get the second goal."
In Arteta's first home game in charge of Arsenal against Chelsea, his side lost 2-1. One of the Blues' goalscorers, Jorginho, was lucky to have been on the field as he had escaped a second booking for a foul on Matteo Guendouzi.
The Spaniard added that he felt the Gunners had "deserved" to win on Saturday "because the performance was at the level required."
Goal's Charles Watts could not believe VAR did not award Arsenal a penalty:
The Telegraph's Sam Dean felt it was a foul on Pepe, too, but like Arteta he was also critical of Arsenal's failure to build on their lead:
Gabriel Martinelli fired Arsenal in front from close range at the Emirates Stadium on the stroke of half-time, but John Fleck replied in the 83rd minute.
The Gunners have failed to score more than once in five of Arteta's six matches in charge. Of those, the only one they've won was against Championship side Leeds United in the FA Cup.
While they were unfortunate with the penalty decision, it's not something they should be relying on to win games, particularly at home.
Arsenal have won just twice in the Premier League since October 6. If that's to improve, they either need to start hitting the back of the net more regularly or get into the habit of keeping clean sheets, as they've recorded just four shutouts in the league this season.