In 2012, baseball fans witnessed a number of high-profile trades before the deadline in August, many of which had critical post-season implications. Of all those players who changed uniforms during the 2012 season, Ryan Dempster finished the season with the most WAR with 3.6 split between his time in Chicago and Arlington (according to Baseball Reference). He was closely followed by another starting pitcher in Zack Greinke, who traveled from Milwaukee to Anaheim and ultimately earned a combined 3.3 WAR, and first basemen Adrian Gonzalez who split 3.2 WAR between time spent on either side of the country.

These are all fairly impressive WAR totals, but none of them came close to entering the top 50 seasons for players who changed allegiances in the Live Ball Era.

Greatest Traded Seasons Since 1920

Num Name Year Total WAR Team 1 WAR 1 Team 2 WAR 2 1 Rickey Henderson 1989 8.4 NYY 3.4 OAK 5 2 Bobo Newsom 1939 7.9 SLB 0.9 DET 7 3 Tom Seaver 1977 7.7 NYM 2.3 CIN 5.4 4 Mark Teixeira 2008 7.5 ATL 3.9 LAA 3.6 5 Tom Candiotti 1991 6.8 CLE 3.5 TOR 3.3 6 Bartolo Colon 2002 6.8 CLE 4.5 MON 2.3 7 David Cone 1995 6.7 TOR 4.2 NYY 2.5 8 Randy Velarde 1999 6.7 ANA 4 OAK 2.7 9 Carlos Beltran 2004 6.6 KCR 2.2 HOU 4.4 10 Bert Blyleven 1985 6.4 CLE 3.9 MIN 2.5 11 CC Sabathia 2008 6.4 CLE 1.7 MIL 4.7 12 Doyle Alexander 1987 6.3 ATL 2 DET 4.3 13 Aurelio Rodriguez 1970 6.2 CAL 0.8 WSA 5.4 14 Bert Blyleven 1976 6.2 MIN 1.2 TEX 5 15 Mark Langston 1989 6.2 SEA 1.4 MON 4.8 16 Scott Rolen 2002 6.2 PHI 3.5 STL 2.7 17 Virgil Trucks 1953 5.9 SLB 2.1 CHW 3.8 18 Mike Piazza* 1998 5.9 LAD 0.8 FLA -0.1 19 Harry Walker 1947 5.8 STL -0.2 PHI 6 20 Denny Neagle 1996 5.8 PIT 5.9 ATL -0.1 21 Placido Polanco 2005 5.8 PHI 1.7 DET 4.1 22 Claude Passeau 1939 5.7 PHI 0.7 CHC 5 23 Rich Harden 2008 5.7 OAK 2.4 CHC 3.3 24 Roy Oswalt 2010 5.7 HOU 2.5 PHI 3.2 25 Ray Boone 1953 5.6 CLE 1.2 DET 4.4 26 Lou Brock 1964 5.6 CHC 0.1 STL 5.5 27 Earl Wilson 1966 5.6 BOS 1.3 DET 4.3 28 Manny Ramirez 2008 5.6 BOS 2.2 LAD 3.4 29 Red Schoendienst 1957 5.5 NYG 1.7 MLN 3.8 30 Gaylord Perry 1975 5.5 CLE 1.4 TEX 4.1 31 Fritz Ostermueller 1944 5.4 BRO 0.8 PIT 4.6 32 Keith Hernandez 1983 5.4 STL 1.2 NYM 4.2 33 Randy Johnson 1998 5.4 SEA 1.2 HOU 4.2 34 Hunter Pence 2011 5.4 HOU 3.2 PHI 2.2 35 Red Barrett 1945 5.3 BSN -0.1 STL 5.4 36 Minnie Minoso 1951 5.2 CLE 0.3 CHW 4.9 37 Willie McGee 1990 5.1 STL 4.3 OAK 0.8 38 David Wells 1995 5.1 DET 4.4 CIN 0.7 39 Cliff Lee 2009 5.1 CLE 4.1 PHI 1 40 Roy Cullenbine 1945 5.0 CLE 0.2 DET 4.8 41 John Tudor 1988 5.0 STL 3.8 LAD 1.2 42 David Cone 1992 5.0 NYM 3.4 TOR 1.6 43 Matt Holliday 2009 5.0 OAK 2.8 STL 2.2 44 Doug Fister 2011 5.0 SEA 2.6 DET 2.4 45 Goose Goslin 1930 4.9 WSH 0.4 SLB 4.5 46 Mark McGwire 1997 4.9 OAK 2.9 STL 2 47 Curt Schilling 2000 4.9 PHI 2.5 ARI 2.4 48 Scott Rolen 2009 4.9 TOR 3.7 CIN 1.2 49 Sal Maglie 1956 4.8 CLE 0.1 BRO 4.7 50 Rickey Henderson 1993 4.8 OAK 4.4 TOR 0.4

The amazing Ricky Henderson bookends the list at both #1 with his remarkable 1989 season in which he was packaged by the Yankees back to Oakland, and again at #50 with his subsequent move in 1993 from Oakland to Toronto.

Mark Teixeira's 2008 season at #4 was just 4 years ago and is likely still very fresh in our memories. Teixeira was worth 3.9 WAR in 105 games with Atlanta and a strikingly similar 3.6 WAR with the Angels in just 53 games after the trade.

(EDIT: This was not the year the Texas Rangers sent Teixeira to the Atlanta Braves for one of the heftier prospect returns of the decade, one that included Elvis Andrus, Neftali Feliz, Matt Harrison and Jarrod Saltalamacchia as an earlier version of this article alleged. That trade occurred in 2007.)

#7 was one of David Cone's infamous mercenary-for-hire seasons in which he was traded from the Blue Jays to the Yankees, and at 6.7 WAR, and it was clearly his best.

CC Sabbathia also makes the list courtesy of an outstanding season from 2008, one in which he nearly single-handedly pushed the Milwaukee brewers into the post-season with an almost flawless final stretch to end the summer.

Mike Piazza's strange 1998 season ultimately landed him in three different cities and shows up at #18. Piazza was traded from the Dodgers to the Marlins on May 14th of that season, then just eight days later was sent packing yet again to the New York Mets. Ultimately Piazza would finish the season with an impressive 5.9 WAR.

Hunter Pence is the proud owner of one of two seasons from 2011 to make the cut, splitting time between Houston and Philadelphia in his breakout 5.4 WAR campaign. Doug Fister's efforts between Seattle and Detroit in 2008 also earn him a seat at the table in a 5-way tie for 40th place with 5 WAR. Carlos Beltran's move from New York to San Francisco of that same year just missed the list with a solid 4 WAR accumulated with both clubs.

Are there any recent trades you are surprised did not make the cut?

All data courtesy of Baseball-Reference.



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