Kurt Summers Rich Hein / Sun-Times

CHICAGO SUN TIMES / Laura Washington

“Be prepared for a curveball.”

That was the advice Kurt Summers heard from his boss, Michael Sacks. Sacks, of Grosvenor Capital Management, is a confidant of Mayor Rahm Emanuel. Summers had been summoned to City Hall.

Emanuel’s pitch: to appoint Summers the next treasurer of the City of Chicago.

“I was floored,” Summers recalled last week.

Emanuel tapped Summers, 35, to replace Stephanie Neely, who is leaving the post to take a job in the private sector.

It came in just enough time to get Summers on the ballot for the Feb. 24 municipal election, with the gift of incumbency for good measure.

Engineer the replacement for a top political job before we even know there’s an opening. A curveball to deprive voters of a real choice is so Chicago.

Summers rejects that, pledging to work hard for the vote, and that he was “made for” the job. The Harvard MBA is a senior vice president at Grosvenor, has served in leadership roles at Goldman Sachs and McKinsey & Co., and co-chaired Emanuel’s task force that brought the George Lucas Museum to Chicago. He served as chief of staff to Cook County Board President Toni Preckwinkle, his chief political mentor. The city’s power elites are rolling out the cash, troops and clout. It’s a done deal.

“None of what makes me tick is determined by where I went to business school or that I worked at an investment bank,” he said as we strolled toward 48th Street and King Drive, down the block from the Harold Washington Cultural Center.

Harold’s legacy is in Summers’ blood. Sam Patch, a legendary community activist and close adviser to Chicago’s first black mayor, is Summers’ grandfather. Summers soaked up the political lore at “Grandad’s” from age 4.

Patch exposed him to the “greats” of black political history. “I would sneak downstairs and . . . do anything I could to just be in the room. I called him Uncle Harold.”

On this chilly, gusty morning, his memory lane is dotted with elegant vintage greystones next to gritty, empty lots.

Modest, soft-spoken and energetic, Summers groaned at the mention of his childhood nickname: “Mashed Potatoes.”

“I was a cute little chubby-cheeked kid, had a mashed-potato complexion.” That kid lived in “G-Town,” named for the notorious Gangster Disciples. “You basically couldn’t walk down the block without getting hemmed up by somebody if you weren’t in their gang.”

Summers conquered the G’s, guns, drugs and dead ends, cradled by the community, neighbors, aunts, granddad. He got out — and wants to give back.

“The way you survive those things is you learn how to survive here, and that’s as important to my story, what prepares me to be a leader in the city, as anything else I’ve done.”

He wants to leverage the $7 billion the Treasurer’s office manages to lure bigger capital and fill those empty lots in Bronzeville and other underserved communities.

Preckwinkle and Emanuel are archenemies, but the Summers nod left Preckwinkle “pleasantly surprised.”

Summers claims there were no backroom deals. Maybe.

Emanuel is eager to boost this rising African-American star. It helps repair his shaky relationship with black voters and sets up an ideal successor for 2019. Maybe sooner if Emanuel heads back to Washington, or goes for higher office.

In Chicago, there’s always another curveball just around the corner.