Arsenal boss Mikel Arteta was delighted with Emile Smith Rowe in midweek against Luton.
The midfielder was superb in the 2-1 win.
Ahead of Saturday's trip to Brighton, Arteta said: "I was very pleased with the result and performance.
"When you make changes there is always a possibility [of losing], but the boys were really good.
"[Emile] Smith Rowe was really strong in the game and showed he is one great player when he is fit and playing at this level."
Asked about Kai Havertz, he added: "I am very pleased with him. He has incredible qualities in the attacking phase as well as in link-up play.
"His contribution defensively is outstanding with the work rate he puts into the team. He has more games to come and he will be trying to improve his numbers. It is just his first season for us and has been moving in different positions. He is very intelligent."
