Ramsey's outstanding start to the season continued at Swansea City as he scored one and set up another in Arsenal's 2-1 triumph at the Liberty Stadium.
The Wales international has now netted eight goals in nine appearances for Arsenal this season, and his man-of-the-match display proved crucial as Wenger's men moved to the top of the Premier League table.
When quizzed about the 22-year-old's performance, a delighted Wenger told Sky Sports: "Much like the team, he had a difficult start.
"But he became stronger. He had an outstanding second half today and scored again. What can you say?
"There's still a lot of improvement to come from him."
Gnabry scored Arsenal's opening goal and proved their main attacking threat during a dull first half that saw neither side register a shot on target.
"He is 18 years old," he said. "Early quality on the pitch is what he is showing. We are giving him confidence and he had another good game today."
"The first half was quite difficult. I felt we were a little bit slow in our combinations and Swansea were a little sharper than us," he added.
"The second half we were much stronger. We took advantage of the chances we created. We have substance in the team and you could see that today in the second half.
"We came out with purpose and won the game. That was important.
"Our spirit has been tested after the first home game (against Aston Villa) and the way we responded…it is very positive."
Arsenal's next test will come against Rafael Benitez's Napoli in the UEFA Champions League at Emirates Stadium on Tuesday.
