By Josh James
Extra-time goals from Emile Smith Rowe and Pierre-Emerick Aubameyang got our FA Cup defence off to a winning start.
Smith Rowe had earlier had a red card - rightfully - overturned after VAR intervention and stayed on the pitch to break the deadlock, just when penalties looked to be looming after 110 minutes of goalless football.
The youngster continued his excellent recent form with a sweet shot in off the post, from fellow substitute Alex Lacazette's knock down, to break Newcastle's resistance.
And Aubameyang made it six goals in just four FA Cup matches to make sure of our place in the fourth round.
We started strongly in sub-zero temperatures at Emirates Stadium. Reiss Nelson - a late replacement for Gabriel Martinelli who had picked up an ankle injury during the pre-match warm-up - had our first shot on goal inside 60 seconds, but it was easily dealt with by Martin Dubravka.
Moments later he was brought down on the halfway line just as it appeared he was racing through on the counter-attack.
Nicolas Pepe was also full of dangerous intent in the early stages, but it was Aubameyang who had our best chance of the first half. Beating the offside trap just inside the Newcastle half, he sprinted on to a long Cedric Soares free-kick over the top, and forced a smart save from Dubravka. Willian fired the rebound over.
Generally though we were lacking inspiration against a Newcastle side content to sit very deep and make it hard for us to break them down.
When Newcastle did threaten, it was usually from a set piece. We failed to properly clear one such free-kick, and were relieved to see Andy Carroll miss from close range when a misdirected shot fell straight to him unmarked at the far post.
Aubameyang again raced away one-on-one only to skew his shot wide as the game began to open up.
Joe Willock couldn't get enough power on his downward header from Pepe's cross and then the Ivorian shot wide after bursting forward.
We continued to rain the shots in. Aubameyang hit a spectacular long-range volley over while substitute Bukayo Saka curled an effort just off target.
There was drama in injury-time at the end of the 90 minutes. Our defenders were sent forward for a free-kick, but when Dubravka claimed the cross, the visitors were away on the counter-attack. Carroll looked certain to score but Bernd Leno made himself big, made the save, then pounced on the loose ball.
Smith Rowe was shown a red card for a foul on Sean Longstaff, only for referee Chris Kavanagh to overturn it after viewing it again on the VAR monitor.
So we went to extra-time. Granit Xhaka's cracking volley was turned over the bar by Dubravka and Aubameyang had a strong penalty appeal turned down as we most of the running in the first period of extra-time.
Penalties looked inevitable, until Smith Rowe's crisp finish into the bottom corner with 10 minutes remaining.
Aubameyang - our two-goal hero in the final last season - then sealed the win when he tucked home Kieran Tierney's cross from close range.
HOW IT HAPPENED
Mikel Arteta made seven changes to the side that beat West Brom last weekend. Only Bernd Leno, Kieran Tierney, Pablo Mari and captain Pierre-Emerick Aubameyang retained their places.
But it was nevertheless a very strong line-up to kick off our defence of the trophy. Gabriel Martinelli was a late withdrawal in the warm up, so Reiss Nelson joined Nicolas Pepe and Willian in an attack-minded line up, but Thomas Partey was again not included in the squad.
WHAT IT MEANS
We are in the hat for the draw for the fourth round, which takes place on Monday evening. The fifth round draw will also take place at the same time. Fourth round FA Cup matches will be played on the weekend of January 23 and 24.
It's back to Premier League action this Thursday evening, when we host Crystal Palace, looking to make it four league wins in a row. Then we face Newcastle again in the league, the following Monday, also at Emirates Stadium.
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