The newspaper said the 33-year-old DeJesus, earning $4.25 million this season, joined the Nationals from Chicago for a player to be named later.
At the same time, struggling outfielder Roger Bernadina was released, clearing a spot for the 11-year major league veteran, who hitting .250 with six homers through 84 games for the Cubs.
The move represents a salary upgrade in the fourth outfielder position for Washington, which remains 9 1/2 games out of a National League wild card slot with 39 games left in the season.
Bernadina, 29, was hitting .178 with 44 strikeouts through 85 contests.
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