Baseball’s second half is officially off to a surprising start, thanks to the Windy City.

The Chicago Cubs and Chicago White Sox sprang an all-Chicago blockbuster trade on an unsuspecting baseball world Thursday morning as the White Sox sent top starter Jose Quintana to the Cubs for a package of prospects including prized minor-league outfielder Eloy Jimenez.

Quintana has been involved in trade rumors dating back to the winter meetings. He has struggled with consistency this season, though, going 4-8 with a 4.49 ERA and 95 ERA+ over 18 starts.

The Cubs, however, need rotation help and were willing to pay a pretty price to get it as soon as possible. They’ll start the second half of the season 5 1/2 games behind the Milwaukee Brewers in the NL Central. Considering the Brewers were also interested in obtaining Quintana, it would appear the Cubs have already recorded one victory over their rivals.

Jimenez, 20, is the fifth-best prospect in baseball, according to Baseball America and renowned for his power. Big League Stew readers might remember his Roy Hobbs-type light-tower shot from a Single-A Home Run Derby a few weeks ago.

Jimenez will be joined by RHP Dylan Cease and two infielders Matt Rose and Bryant Flete.

On the surface, this looks like a good trade for both squads. The Cubs starters have been struggling and they get the 28-year-old Quintana under team control through 2020.

The Sox, meanwhile, get more big pieces for their massive rebuild. GM Rick Hahn has now turned Quintana, Chris Sale and Adam Eaton into a stable of prospects headlined by Jimenez, Yoan Moncada, Michael Kopech, Lucas Giolito and Reynoldo Lopez.

The Cubs and White Sox have made franchise-altering trades with each other before.

In 1998, the White Sox obtained Jon Garland from the Cubs in exchange for pitcher Matt Karchner. Garland would end up being one of the Sox’s history-making starters in the team’s run to the 2005 World Series title.

In 1992, the Cubs got a guy by the name of Sammy Sosa in exchange for George Bell. While Bell helped the White Sox to the 1993 AL West division title, Sosa would, for better or worse, become a big part of Cubs history over the following decade.

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