In December of 1976 the Brewers said farewell to one of their best young players, trading catcher Darrell Porter along with pitcher Jim Colborn to the Royals for catcher Jamie Quirk, outfielder Jim Wohlford and a player to be named later. Losing Porter, a former and future All Star catcher, and Colborn, a former 20-game winner, was a tough blow to take and Quirk and Wohlford didn't provide much value in exchange. Thankfully, the player to be named later turned out to be a big part of the deal: On this day in 1977 the Royals sent pitcher Bob McClure to Milwaukee to complete the trade.
McClure, who was 24 years old at the time, had pitched just 20 games in the majors over two seasons as a Royal. He won a job in the Brewer bullpen right away, though, and posted a 2.52 ERA over 68 relief appearances in 1977. Over ten seasons as a Brewer he pitched in 352 games (73 starts) with a 3.97 ERA. He also pitched in nine playoff games in 1981 and '82, recording two saves in the World Series.
The Brewers traded McClure to the Expos in 1986, and he eventually pitched eight more major league seasons as a member of five teams. He's currently working as the pitching coach of the Red Sox, and spent some time with the Royals before that.