Emile Smith Rowe came off the bench to break the deadlock in extra-time as Arsenal - the competition's defending champions - made hard work of seeing off Newcastle in the third round of the FA Cup.
The 20-year-old, who was shown a straight red card in normal time only for VAR to intervene and overturn the decision, finally made the breakthrough in the 109th minute with a smart finish, after coming on as a second-half substitute.
With the talented youngster omitted from the starting XI, Arsenal had really struggled to break down a resilient Newcastle side, with Pierre-Emerick Aubameyang going closest in the first half.
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Despite Arsenal controlling the possession, it was Newcastle who created the best chances in normal time, and both fell to Andy Carroll. The 32-year-old inexplicably shot wide from just yards out in the 56th-minute. And as the game became really stretched, he was denied at point-blank range by Bernd Leno in stoppage-time.
Newcastle would rue such profligacy, with Smith Rowe latching onto a ball inside the visitors' area and slotting it past the returning Martin Dubravka with a smart finish to finally break the visitors' resistance four minutes into the second period of extra-time.
And with Steve Bruce's men tiring, Aubameyang made Arsenal's place in the fourth round safe with a cool finish from the excellent Kieran Tierney's cross in the 117th-minute.
TALKING POINT - Smith Rowe the difference as youngster shines once more
After such a packed winter schedule, the last thing either manager needed was an extra period of 30 minutes. But that's exactly what we had to endure after the preceding 90 minutes failed to produce the kind of memorable affair both sides had conjured up in the past - remember Arsenal's 7-3 victory in 2012 and the 4-4 draw a year earlier?
With Smith Rowe and Bukayo Saka starting on the bench, Arsenal were sluggish and predictable. The fringe players failed to make an impression, but none more so than Reiss Nelson, who was called into the team after Gabriel Martinelli was injured in the warm-up. This was another reminder to Arteta of who his most important players are - and they both made a difference.
Defeat will be hard to take for Steve Bruce, whose side had shown real character and steel to hold Arsenal at bay. Had Carroll buried one of his two golden opportunities, Newcastle would have taken the plaudits.
MAN OF THE MATCH - Emile Smith Rowe (Arsenal)
Introduced just short of the hour-mark with Arsenal desperately lacking creativity, Smith Rowe produced the kind of performance we have come to expect. He was direct, injected pace into the front line and generally looked dangerous every time he received the ball.
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Arsenal: Leno 7, Cedric 5, Luiz 6, Mari 6, Tierney 8, Elneny 7, Willock 6, Pepe 6, Willian 6, Nelson 5, Aubameyang 7.. subs: Maitland-Niles N/A, Xhaka 6, Saka 7, Smith Rowe 8.
Newcastle: Dubravka 7, Krafth 6, Lascelles 6, Clark 6, Dummett 7, Hayden 6, S Longstaff 6, Hendrick 6, Almiron 5, Joelinton 4, Carroll 5.. subs: Ritchie 6, Gayle 5, Yedlin 5, Murphy 5, Anderson 5.
25' - Arsenal chance! Finally, some goalmouth action! Luiz takes a quick free-kick, lifting a wonderful ball over the top for Aubameyang to run onto. He shoots powerfully at goal from a tight angle, Dubravka makes the save and Willian fires over from the rebound.
56' - How does Carroll miss?! Newcastle win another free-kick in a wide area. Tierney's headed clearance is poor, Hendrick's shot falls to Carroll at the back post, and it looks a simple finish. However, the striker somehow pokes it wide from just yards out! The linesman's flag is raised, but the replay shows he's actually on, and it would have gone to VAR and counted had he scored. A real let off for Arsenal!
90'+2 - Carroll should win it for Newcastle! Leno parries Anderson's shot into the path of Carroll, whose shot is blocked by the Arsenal goalkeeper. And Leno then gathers himself quickly to throw himself onto the ball before Carroll can score with the rebound!
90'+3 - Red card overturned! Smith Rowe is shown a straight red card for a tackle on Longstaff, but that looks really harsh. The referee is going to the screen to look at the incident... and correctly overturns his decision. It's just a yellow for the Arsenal man.
109' - GOAL! Arsenal 1-0 Newcastle (Emile Smith Rowe): The deadlock is finally broken! It's Smith Rowe, who thought he was sent off in normal time before the decision was overturned, who grabs what could be the winner! Arsenal win the ball in midfield and the youngster controls the ball beautifully before slotting it past Dubravka.
117' - GOAL! Arsenal 2-0 Newcastle (Pierre-Emerick Aubameyang): That will do it! It's brilliant from Tierney, who busts a gut to get on the end of Xhaka's pass. He lifts in into the middle to find Aubameyang, who finishes with a simple tap-in for another FA Cup goal for the Arsenal skipper.
Arsenal have now progressed from 24 of their last 25 FA Cup third round ties, failing only against Nottingham Forest in 2018 in this run.
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