The new number nine is now one of three Gabriels at the club.
He told arsenal.com: “Now it's three! There's a lot of jokes with us now, but they are very good guys. I'm so happy for them because they deserve to be in a big club like Arsenal, and they did so well last season. I'm so happy to be here with them."
Martinelli is now a current international teammate of Jesus and the new man is looking forward to the pair linking up again in the Premier League.
“I'm so happy with him," Jesus said. “He went to train with us in the national team [in the summer of 2019] and was in the Copa America in Brazil. We saw him and his qualities, and he can do things other players cannot.
“When I saw him come to Arsenal I was not surprised because I knew he had the quality to play in a big club in Europe and Brazil. I'm so happy for him because he deserves this because he's a quality player. The next season I was following him, watching videos and games."
Jesus has also had plenty of battles with the Gunners' centre-back Gabriel over the past two seasons, and knows first-hand how tough an opponent he is.
He only needed a single word to sum up their previous encounters: “Difficult. He's so strong. I have played against him a couple of times. He's a very difficult defender, but has the quality to play as well."
With the World Cup just five months away, the prospect of three Arsenal players in the Brazil squad could be very real indeed, and that's something Jesus hopes will become a reality should the trio start the season strongly.
“It would be massive for us personally because I played in the last World Cup, so I know it's so good to be there. With Brazil, we grew up seeing players like Ronaldo, Ronaldinho, Kaka and Romario, and then we wanted to be the next ones.
“The World Cup is here now and we have the opportunity to play there together from the same club – all three Gabriels!"