The city authorities and the club's president had proposed renaming the San Paolo Stadium within hours of Maradona's death on 25 November.
"Your quick departure didn't let me say it to you, so I will just write: I love you, Diego."
The probe was triggered by concerns raised by three of Diego Maradona's daughters Dalma, Giannina and Jana over the treatment he received for his heart condition.
New Zealand captain Sam Cane symbolically place the shirt on the ground as a mark of respect ahead of their traditional haka.
The images distributed across social media created outrage, even death threats, across a nation that venerated Maradona, who died Wednesday of a heart attack at age 60.
Leagues around Europe will honour former Napoli and Barcelona player Diego Maradona in different ways after his passing on Wednesday.
Carlos Bilardo took Argentina to three World Cups, from 1982 to 1990. They won the title in 1986 with Maradona at the heart of the team.
Built after World War II, the stadium was named for St. Paul according to the legend that the apostle docked in the surrounding Fuorigrotta area when he reached current-day Italy.
To name FIFA's player of the 20th century, Pelé was the pick of experts. Maradona was the people's choice as the winner of an online vote. So they shared the award and continued to bicker in public.
Maradona was treated as a deity for the way he led Napoli to its only two Serie A titles — in 1987 and 1990 — and raised the spirits of the southern Italian city, which remains far removed both geographically and socio-economically from the country's football capitals of Milan and Turin.
Diego Maradona passes away: A player with no distinguishable physical advantage, Argentine legend was the finest dribbler of his time
The finest dribbler of his generation, Diego Maradona mounted challenges like a rooster in heat, chest puffed out, angled elbows bent inwards, with a bit of his tongue sticking out.
Diego Maradona scored some of the most famous — and thrilling — goals in football history. Here are his five more spectacular ones:
Diego Maradona's most famous goals came within four minutes of each other on 22 June, 1986 in Mexico: one was voted Goal of the Century. The other one is even more famous.
Diego Maradona passes away: Troubled genius was famous for composure on football and for frequent lack of control off field
Short, powerful and quick, Maradona was also a ferocious and astute competitor who refused to be intimidated even though many opponents tried.
Diego Maradona, Argentine football legend and 1986 World Cup winner, passed away in Buenos Aires on Wednesday. He was 60.
The 1986 World Cup-winner was recently hospitalised, being released on 12 November, eight days after undergoing surgery to remove a blood clot on his brain.