Borbon was hitting .202 with one home run and three RBI in 104 at-bats. Murphy, who is 30, was hitting .265 with 12 home runs at Iowa. He has played in parts of seven seasons in the major leagues.
Chicago has now used 47 players on the big league roster in 2013. The club record is 53.
Borbon made a fatal baserunning decision on Friday that sealed his fate. With the Cubs trailing by four runs in the ninth inning, Borbon tried to advance from second base to third on a pitch in the dirt by former Cub Carlos Marmol. Borbon was thrown out easily as the Los Angeles Dodgers went on to win 6-2.