Just 55,000 of the 80,000 seats inside the San Siro had been sold for the 'Derby della Madonnina' by Wednesday morning, which has been attributed to fan dissatisfaction at AC Milan's decline and the struggling Italian economy.
With just four days to go until what is historically one of European club football's blue riband fixtures, club captain Massimo Ambrosini and vice president Adriano Galliani have appealed to fans to attend the game.
"Guys, a derby without you has no meaning," said Massimo Ambrosini in a video on the club's website. "Buy tickets because we can all go together to the stadium to win this most important of games."
Galliani added: "It might be the recession, the economic crisis or decline in results of Milan and Inter, but for the first time in 26 years ticket sales are slow for the derby.
"We're late, late, late. I appeal to the tifosi (fans) to fill the stadium."
Last season a crowd of 79,612 saw title-challenging Milan beaten 1-0 by a Diego Milito goal, while the previous year 80,000 cheered on the eventual champions as they hammered Inter 3-0.
Yet just over 28,000 saw Milan win their first and only home game of the season so far, 2-0 against Cagliari on Sept. 26, the lowest attendance since Silvio Berlusconi took over the club in 1986.
Disappointing performances, Italy's economic problems and fans' disaffection at the sales of Zlatan Ibrahimovic and Thiago Silva have been blamed for keeping supporters away.
Tickets for Sunday's game are now on sale to those who do not have the controversial "tessera del tifoso", a national supporter ID card scheme that was created with the aim of curbing violence but has angered fans' groups.
Milan are 11th in Serie A with seven points, five behind third-placed Inter and nine behind leaders Juventus.