Nunez opened his account for Benfica with a three-goal haul as the Portuguese powerhouse defeated Lech Poznan 4-2 in their Europa League opener on Thursday.
The 21-year-old Uruguay forward became Benfica's most expensive signing when he arrived from Almeria in a €24million deal in September.
Jesus is already bracing for Nunez's exit, tipping his transfer fee to surpass the club-record €126m Benfica received from Atletico Madrid for Joao Felix last year.
"We got it right. We must not forget that he is a kid, he is 21 years old, there is a lot about the game that he does not know yet. He will learn with me and Benfica," Jesus told SportTV.
All this decision-making ability, finishing and speed… He was Benfica's most expensive purchase, and when there is no pandemic, he will be the most expensive sale. He will be a world-class player.
"Unfortunately for me, maybe I will lose him in a short time."
Benfica's Nunez scored with all three shots on target away to Polish side Lech Poznan.
Nunez made it 2-1 for Benfica three minutes prior to half-time before netting his second of the match on the hour-mark as he completed his hat-trick in the third minute of stoppage time.
"Three goals? It means a lot to me," Nunez told SIC. "When I don't score, I try to help the team. I haven't scored for five games, but I worked for the team.
"From the first moment the team gave me confidence. They think I deserved these goals. I am very happy.
"I thought I was going to score my first goal. I didn't expect the three goals, but thankfully. Now it's time to continue working with humility. It's a difficult series now and we have to prepare ourselves in the best way."