Rangers in the wild card race. With infield defense proving to be their Achilles' heel, they made a four-team trade deadline deal on July 31 that landed Mientkiewicz and Montreal Expos shortstop Orlando Cabrera with the Boston Red Sox, and sent Justin Jones to the Twins. Coincidentally, the Twins were playing a home series against the Red Sox at the time. On July 30th, 2004, Mientkiewicz went 2-4, scoring one run as a member of the Minnesota Twins. The next day, July 31, 2004, Mientkiewicz was in the visiting dugout as a member of the Boston Red Sox, and started at first base and hit sixth in the lineup. The Red Sox also sent Nomar Garciaparra and Matt Murton to the Chicago Cubs, and the Cubs sent Francis Beltrán, Alex Gonzalez and Brendan Harris to the Expos as part of this trade. Mientkiewicz and Cabrera proved valuable additions to their new franchise as the Red Sox surged to within three games of the Yankees by the end of the season, and took the A.L. wild card by seven games over the Oakland A's. On August 16, Mientkiewicz made an emergency start at second base, a position he had only ever played four times in the minor leagues, and never in the majors. Mientkiewicz went 4-for-10 in the post-season. He did not appear in any of the first three games of the 2004 American League Championship Series that the Red Sox lost to the New York Yankees; however, he appeared in all of the final four that they won in their come-from-behind series win. When St. Louis Cardinals shortstop Édgar Rentería grounded back to pitcher Keith Foulke, who trotted toward first base and underhanded the ball to Mientkiewicz to complete Boston's four-game sweep of the World Series, Mientkiewicz kept the ball, as dictated by baseball tradition. As Boston had not won a World Series in 86 years, the ball symbolized the end of the so-called "Curse of the Bambino", and was of considerable interest to memorabilia collectors. Controversy resulted when the Red Sox asked for the ball's return, and Mientkiewicz refused to give it back. Shortly after his January 27 trade to the New York Mets, Mientkiewicz and the Red Sox reached an agreement that the Red Sox would hold the ball temporarily and could display it across New England, along with the World Series trophy. The agreement called for Mientkiewicz