#4 - Cardinals send three stars to Milwaukee
By names alone, this trade could be even higher on the list. The only saving grace for St. Louis in this awful deal is that each of the players had relatively short careers following the trade.
After acquiring Bruce Sutter from the Cubs, the Cardinals sent Rollie Fingers, Ted Simmons, and Pete Vuckovich to the Brewers for David Green, Dave LaPoint, Sixto Lezcano, and Lary Sorensen. All four of those players ended up being decent players for St. Louis, but each of the players they sent out continued to play at a high level.
Fingers was acquired that same offseason by St. Louis and dealt to the Brewers just days later, and ended up having a 1.04 ERA and 28 saves in route to the Cy Young and MVP in 1981. He'd become an All-Star again in 1982 and then only pitch two more seasons following that.
Ted Simmons was a Hall of Fame catcher and produced two more All-Star quality seasons himself following the trade, though outside of that, he was not much more than just a good catcher for the other six seasons he played. after the trade.
Vuckovich followed up Fingers' Cy Young with his own in 1982, but also only pitched three more seasons following that. All in all, St. Louis gave up two future Cy Young award winners and a two-time All-Star catcher in this deal, while only getting servicable players back.
I can totally see this trade deserving a higher ranking on the list, but unfortunately, we've entered some territory where all of these trades will look really bad.