The Chicago White Sox are reportedly adding prized closer Craig Kimbrel in a trade with the Chicago Cubs, instantly upgrading their bullpen for the stretch run.

ESPN's Jeff Passan says the crosstown rivals are finalizing the deal. The price is steep: The White Sox will send second baseman Nick Madrigal and right-handed pitcher Codi Heuer to the Cubs. Madrigal had been the starting White Sox second baseman until he went down with an injured hamstring, and was a top draft pick in 2018.

The sport’s most accomplished active closer, Kimbrel is once again at the top of the game at age 33. He joins a team that already boasts star closer Liam Hendriks (2.58 ERA, 25 saves so far in his first year with the White Sox). Cruising toward a playoff berth with an eight-game lead over a fading Cleveland team, the White Sox are building more for October than for any sort of pennant race.

After two rough (and shortened) seasons with the Cubs, Kimbrel has reverted to fire-breathing Kimbrel form. Sporting a 0.49 ERA with 23 saves, he’s striking out almost 47 percent of batters he faces — hallowed territory he has tread about as often as everyone else in baseball history combined.

Put succinctly: The best seasons thus far in his Hall of Fame-track career are 2012 (1.01 ERA, 50.2 K%) and 2017 (1.43 ERA, 49.6 K%), and he’s looking game to threaten them. In addition to the league-leading strikeout rate, he has the best FIP and lowest opponent batting average among relievers in 2021.

Kimbrel's contract includes a team option for 2022.

The deal is part of a sell-off on the North Side. The Cubs previously traded Anthony Rizzo to the New York Yankees on Thursday, and sent Kimbrel's past and future bullpen-mate Ryan Tepera to the White Sox. The Cubs also sent Javy Baez to the Mets on Friday.

With the addition of Kimbrel and Tepera, manager Tony La Russa will add more dominant arms to Hendriks and the young Michael Kopech — a likely future starter being used in relief.

Madrigal is an elite contact hitter who has batted .317 in the first 83 games of his young big-league career. He was viewed as a key piece in the burgeoning White Sox core before the deal. Though he has been injury prone so far, he figures to play a big role in the next phase of the Cubs' trajectory.

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