The Jug was discovered by Hubbard head coach Elton Harris at a rummage sale in South Bend in 2001. "The people there told me it was a jug you put moonshine in," he said.
Harris painted it dark brown, added Robeson and Hubbard in yellow lettering to the sides and glued to the top a small gold football player statue, ripped off from a participation trophy that was never claimed.
And, unlike the Little Brown Jug that the University of Michigan and University of Minnesota vie for, which contains colorful logos and each year's game scores between the football teams, Chicago's prep version is quite dull.
"And we're going to leave it just as it is," said Robeson coach Fabray Collins, 52, of Englewood.
Collins and Harris' squads will battle for the Jug for the 10th time at 4 p.m. Friday at Stagg Stadium, 1035 W. 74th St.
Both coaches graduated from Robeson, an Englewood school located a few miles from West Lawn-based Hubbard. They created the Jug to make the teams' rivalry "more valuable than just a regular game," said Collins, who briefly played for the Minnesota Vikings in 1987.
"Our teams' players hang out all the time," Harris, 53, said. "We go to football camps together, and all the kids around here know each other."
They also wanted to honor Robeson's former legendary coach Roy Curry by naming the game the "Roy Curry Bowl." Curry, 73, has had 23 former players coach football in the Public League, including current head coaches Collins, Harris, Jason Richardson at Julian High School and Terry Jones at Perspectives Charter Academy.
"It means a lot to me because these are my guys and they think that much of me to name the game after me," said Curry, of Calumet Heights.
In 34 years at Robeson, Curry led the Raiders to a 241-94 record. He also remains the only coach to ever guide a Public League team to a state championship game, which Robeson lost 16-12 to Rockford Guilford in 1982.
Under Harris, Hubbard has come close to winning the IHSA playoffs, reaching the state semifinals twice and quarterfinals another two times. The Greyhounds had qualified for the postseason for Harris, the coach since 1995, every year until 2012, when they also lost the Jug to Robeson for the first time.
Harris, of South Shore, visits his alma mater frequently and consistently sees the Jug sitting in the school's main office. He jokingly said he's thought about stealing the Jug and returning it to Hubbard, where a piece of paper with the words "Brown Jug" currently rests inside the school's trophy case.
Instead, he hopes his 2-2 Greyhounds earn the Jug by beating the 3-1 Raiders on the field.
"Our players will go hard for the Jug," Harris said. "And may the best team win."