Unai Emery's side advanced to the last four on Thursday as Alexandre Lacazette's goal sealed a 1-0 win in Napoli and a 3-0 aggregate success.
Arsenal face Valencia in the semi-finals, with Emery aiming to win his fourth Europa League title and seal Champions League qualification in the process.
That would be an uplifting conclusion to Emery's first season with Arsenal, but if they fall short in the Europa League, the Gunners still have another route to the Champions League via a top four finish in the Premier League.
Currently in fourth place above Chelsea on goal difference, Arsenal have no margin for error in the league, but defender Maitland-Niles says his team have matured as a result of their European exploits and are now better at closing out matches.
"It's a tough league in England. We're learning different methods in Europe because sometimes we need to be more like the foreign teams and just grind out results. It's going well at the moment," he said.
"I think we're gelling together very well. The manager is working with a back four, a back five, so we all know positionally what to do, not to dive in the box and not to give silly fouls away around the box as well.
"We dug deep (against Napoli). You can score as many goals as you want but if you don't defend properly then the game could go either way."
Since Hector Bellerin suffered a serious knee injury, Maitland-Niles has become Emery's first-choice down the right, whether as an orthodox right-back or in the wing-back position he played in Naples.
Pat on the back
England Under-21 international Maitland-Niles praised the way Emery has nurtured his talent so far and also worked to improve the squad as a whole.
"That's what you need, for the manager to pat you on the back when you don't do well," he said ahead of Palace's visit to the Emirates Stadium.
"And when you do well, to pat you on the back even harder and say 'look, this is fantastic'. And he's done that throughout the whole season for me.
"The manager has given us a lot of confidence. He's backing us and he believes in us so much."
The only issue for Arsenal in Naples was an injury to Wales midfielder Aaron Ramsey that will rule him out for up to three weeks.
Ramsey limped off with what Emery described as a muscular injury.
Ramsey will sign for Juventus on a free transfer when his Arsenal contract at the end of the season.
Asked on his way to the team coach after the game if he would be okay, the 28-year-old replied: "We'll see".
"I was speaking to him about 30 minutes ago and we were speaking about that - 'Maybe in two or three weeks, I can play some matches'," Emery said.