LONDON • There were two rookie coaches hopping around on the touchline and both will feel they have spent a lifetime in management after this emotional Premier League roller coaster which ended 2-2 on Tuesday.

While Frank Lampard seethed at Chelsea's lack of conviction at both ends of the pitch, Arsenal's Mikel Arteta wondered what on earth he is going to do with Shkodran Mustafi and marvelled at the fearlessness of Gabriel Martinelli.

It was that sort of night at Stamford Bridge, absorbing and bonkers in equal measure, and in the end it was difficult to know whether to focus on Chelsea's sense of bewilderment or Arsenal's joy.

The Gunners' new manager hopes the resilience his side showed in twice coming from behind while a man down proves a "stepping stone" to a brighter future.

Arsenal remain 10th in the Premier League, 10 points behind fourth-place Chelsea (40) but while a point may be too little for their hopes of a return to the Champions League, the manner in which it was achieved gave him cause for optimism.

"Time will tell if this is a stepping stone, but at least I saw a reaction," said Arteta. "I demand from the players that they never give up. We have to keep playing with the spirit we showed in every game. I'm proud of the way they reacted.

"The spirit, character, fight and leadership was there. When someone makes a mistake and someone has to take a red card for him it can happen. What has to happen is you have to stand up for him and every single player did that."

Chelsea have now won just four of their last 12 league games and were guilty of the same lack of creativity at one end, and defensive lapses at the other, that characterised the home defeats by West Ham, Bournemouth and Southampton.

They went ahead with a penalty by Jorginho in the 28th minute, when Tammy Abraham pounced on a misplaced back pass by Mustafi and was brought down by former Chelsea defender David Luiz, who saw red on his return to Stamford Bridge.

However, the Blues' struggles at home continued as they lacked ideas up front, bolstering the argument that they need attacking reinforcements before the transfer window closes.

They also paid for their carelessness when Martinelli, an 18-year-old winger with a wonderfully direct style, hauled Arsenal level with a stunning solo goal after the hour. From a cleared corner, he outpaced Emerson, raced clear after a slip from N'Golo Kante, the last line of defence.

Chelsea's imprecision is hurting their push for Champions League qualification and it spoke volumes that they were incapable of holding on after Cesar Azipilicueta restored their lead in the 84th minute.

They were too loose and Kepa Arrizabalaga's indifferent form was captured by the moment when Hector Bellerin rescued a point for Arsenal with a shot that somehow squirmed beyond the goalkeeper just three minutes later.

A frustrated Lampard said: "We're in fourth position, but I know and we know there should be another 10 points on the board.

"The initiative is on us to be ruthless, to take the chances when they came along."

The Chelsea boss had already spoken of his desire for his team to be more clinical after losing 1-0 at Newcastle last Saturday, with Paris Saint-Germain's all-time top goalscorer Edison Cavani a target.

And a move for the Uruguayan could be even more of a priority after top scorer Abraham had to be helped from the field at full-time, having injured his ankle in colliding with the advertising boards late on.

THE GUARDIAN, AGENCE FRANCE-PRESSE, REUTERS