Emile Smith Rowe and Pierre-Emerick Aubameyang scored in extra time as Arsenal began their FA Cup defence with a hard-fought 2-0 victory over Newcastle United in the third round at Emirates Stadium on Saturday.
After arriving as a second-half substitute, Smith Rowe had a red card rescinded for a tackle on Sean Longstaff in stoppage time following a VAR review.
Aubameyang also found the net from close range in the final minutes of extra time to extend Mikel Arteta's side's winning run to four games in all competitions.
"I was really happy, a bit of a relief for me with the incident before," Smith Rowe told the BBC. "It definitely wasn't intentional -- happy to get the goal and get through to the next round.
"We knew how tough it was going to be, they're a tough opponent. It was about breaking them down. It shows how together we are, we have been working off the pitch to get closer as a group and it shows."
Arsenal, who have lifted the FA Cup a record 14 times, have failed to progress to the fourth round just once in the last quarter of a century.
Arsenal created the majority of the chances through forwards Aubameyang and Nicolas Pepe but the hosts were denied an opening in 90 minutes at the Emirates Stadium.
Striker Andy Carroll missed the target for the visitors from inside the six-yard box in the 56th minute before his efforts on goal in stoppage time were brilliantly blocked by Arsenal goalkeeper Bernd Leno.
"I thought Andy did fantastically well, if he had topped it off by scoring a goal it would have been good for him," Newcastle manager Steve Bruce said.
"A lot of pleasing things, we've had a tough run of fixtures but we dust ourselves down and go again."
The result left Newcastle without a win in seven games in all competitions.
Gabriel Martinelli missed the match after picking up an injury during warm-up, with Arteta pessimistic on the player's prognosis.
"I am gutted," said the Spaniard. "I was in my office before the game and one of the coaches came in and said that Gabi hurt himself, that he twisted his ankle.
"I went to the medical room and he was in tears. He was in a lot of pain and we are going to have to see how he is -- but he didn't look good. He was in pain, so I imagine we are not going to have good news with him."