1. For extended impact on one team, it’s hard to beat the July 2007 trade between the Atlanta Braves and Texas Rangers.
The Braves were in third place in the NL East but hopeful of running down the division-leading Mets, who at the time had them by three and one-half games. So they went all-in on beefing up their lineup, offering the Texas Rangers four top prospects in exchange for first baseman Mark Teixeira. The Rangers, last in the AL West and willing to unload their veteran slugger, bit.
Teixeira certainly helped the Braves. He batted .317 with 17 home runs over those final two months.
But he could not lift the Braves into postseason play, and so when the 2008 trade deadline arrived the Braves packaged Teixeira to the Angels.
The real headline, though, is the haul the Rangers exacted from Atlanta in exchange for Teixeira. That haul included shortstop prospect Elvis Andrus, pitching prospect Neftali Feliz, catcher Jarrod Saltalamacchia, and pitcher Matt Harrison.
As the Rangers gradually built a team that would reach both the 2010 and 2011 World Series, all four of those players emerged as important pieces.
Andrus remained a middle infield linchpin for Texas through 2020, accumulating +29.8 WAR alone.
The math: Teixeira: +6.12 WAR for Atlanta; Andrus, Feliz, Harrison, Saltalamacchia, +48.1 WAR for Texas. Net impact: +54.2 WAR.