Arteta says he's delighted with the young pair.
"I’m really proud of them because they are dealing with a situation that is probably a little unexpected," he said.
"They have had the chance to play in two of the most historic and difficult grounds in the Premier League and both responded really well.
"What I’ve seen is that they’ve developed in a really positive way. To influence others and raise the standards. They are responsible for that because they have to carry others as well now. Their attitude has been superb.
"It’s not easy when you spend five-six weeks with the first team and then have to play at a different level but this is where they are at the moment and they’re going to have more chances because they have conducted themselves in the right way in that sense as well. I think that’s a really important thing.
"Those two (Nwaneri and Lewis-Skelly) are really pushy and demanding! They want to see everything. They want more and more information. They love it and you can tell they are so passionate about it. They see the opportunity and want to grab it with both hands. They are great to work with."