Note that paragraph does not say "Cubs lefthander". It does not say that because today, when the Cubs activated second baseman Darwin Barney from the 15-day disabled list, they gave Davis his unconditional release.
Davis made nine starts for the Cubs this season. Charitably, you could call two of them "good", two "mediocre" and the other five "bad" (or another adjective that might not be printable here). He did have one shining moment, when he limited the powerful Yankees to three hits and one run in 7.1 innings on June 17 at Wrigley Field, receiving the only standing ovation of his brief six-week Cubs career when he was removed from the game.
Barney has been on the DL since June 14. He sprained his left knee the previous day against the Brewers with a slide into the plate (which scored the only run in a 1-0 Cubs victory) and will play using a knee brace. He is in the starting lineup against the Giants, Wednesday night, batting second.