Gabriel completed his move from Villarreal on Wednesday and bolsters Wenger’s options in defence after Mathieu Debuchy was ruled out for three months with a dislocated shoulder, while Laurent Koscielny has only returned to regular action this month after an Achilles problem.
"He is a promising Brazilian defender," Wenger told Arsenal Player.
"Just 24-years-old and we got the work permit. He has good pace, is good in the challenge and is tall, so he can adapt to English football.
"Maybe it will take some time to adapt completely, but overall it is very good to have him. This season he has played every game for Villarreal and we have seen him many times. We are convinced about his quality.
"He is very ambitious, focused and serious. That is important at a club like ours - you need to have a complete focus on your job. He has that.
"I like the players who come from nowhere and show they can adapt. From Brazil, he has adapted to Spain. That means he has already made it and adapted in another country, and so that is another important quality."
Wenger also reiterated his desire to sign central defender this month and admits his options would have been limited even more if injuries continued to pile up.
"We needed some cover, or we would not be responsible," he said.
"We needed another centre-back because we have lost Debuchy. Nacho Monreal can play centre-back and we are a bit short there if something happens, especially with the Achilles of Koscielny since the start of the season.
"[Gabriel] can play right-back and left-back, and that is of course a good quality as well."
