Harvey Barnes emerged from his injury nightmare to spare Newcastle’s blushes as they fought back from two goals down to deny Premier League newcomers Luton victory in a 4-4 thriller.

The Magpies’ £38million summer signing was called from the bench with his side trailing 4-2 at St James’ Park. 

And after Kieran Trippier had given them hope, it was he who smashed home a 73rd-minute equaliser in his first appearance since September.

In a full-blooded encounter, the home side led 1-0 and then 2-1 through Sean Longstaff’s double. 

But after Gabriel Osho and the excellent Ross Barkley had levelled, Carlton Morris’ penalty and a fourth from midweek hat-trick hero Elijah Adebayo looked to have put the visitors in the driving seat.

Newcastle’s fightback extended into 10 minutes of stoppage time at the end of a pulsating contest as they threw everything they had at the search for a winner. 

But the visitors stood firm to take a more than deserved point from a hugely entertaining draw.

The Magpies went ahead with just seven minutes gone when 17-year-old Lewis Miley sprayed the ball out to Trippier, who looked up before picking out the fast-arriving Longstaff and watched as he fired past keeper Thomas Kaminski.

To their credit, the Hatters swiftly set about the task of trying to force their way back into the game with Chiedozie Ogbene repeatedly making life intensely uncomfortable for Dan Burn.

They were back in it with 21 minutes gone when, after Sven Botman had been penalised for a trip on Adebayo, Morris turned Barkley’s free-kick back across goal and Osho headed past keeper Martin Dubravka off the underside of the crossbar.

Luton’s joy was fleeting and after Kaminski could only parry Anthony Gordon’s shot, Longstaff controlled the rebound and drilled into the back of the net.

However, the home side succumbed once again five minutes before the break when Barkley set Alfie Doughty away down the left before making his way into the penalty area to fire into an empty net.

Rob Edwards’ men took a 59th-minute lead when, following a lengthy VAR review, referee Tom Bramall was advised to award a penalty against Burn after he had dragged back Ogbene. 

And Morris scored from the spot at the second time of asking having initially beaten Dubravka before the whistle had gone.

The Hatters were in dreamland three minutes later when, after another pacy break, Barkley slid the ball into the path of Adebayo, who beat Dubravka emphatically to make it 4-2.

However, the Magpies refused to accept defeat and reduced the deficit with 23 minutes to go when Trippier volleyed Bruno Guimaraes’ cross past Kaminski. 

And there was more to come when Miley robbed Barkley and fed Barnes, who steered a left-foot drive into the bottom corner to level.

Jacob Murphy was unable to convert another inviting Bruno cross at the far post with five minutes remaining and Ogbene volleyed straight at Dubravka deep into added time as the spoils were shared.