After the ownership transfer, O'Malley's rivalry with Rickey became very public. O'Malley forbade the speaking of Rickey's name in Dodgers offices with transgressors being subjected to a fine. He abolished Rickey's title of General Manager so that no front office person could perpetuate Rickey's role. In addition, when Rickey assumed the title with the Pittsburgh Pirates, O'Malley arranged for the Dodgers to omit the Pirates from their spring training schedule. Nonetheless, after the transfer, the Dodgers remained successful under O'Malley: they won the National League pennants in 1952, 1953, 1955—the year of their first World Series championship—and 1956. Under O'Malley, the Dodgers were the most overtly political post World War II franchise. In 1951, Brooklyn native and United States Congressman Emanuel Celler's Judiciary Committee investigated whether the reserve clause was in violation of federal anti-trust laws. Celler represented half of Brooklyn in Congress and O'Malley used the local press such as the "Brooklyn Eagle" to pressure Celler into backing off of the issue. During the 1951 season, the Dodgers engaged former West Point varsity baseball player and U.S. Army General Douglas MacArthur to lure war veterans. O'Malley attempted to entice him to take the post of Commissioner of Baseball. After the 1956 season, O'Malley sold Ebbets Field to Marvin Kratter and agreed to lease the stadium for three years.