Rusin was 2-6 in 13 starts with a 3.93 ERA. He and All-Star Travis Wood could be the first Cubs left-handers to make at least 10 starts and finish with an ERA under 4.00 since Ted Lilly (3.83 ERA) and Rich Hill (3.92) did so in 2007.
"The one thing about Chris is he's fearless," Bosio said. "He needs to work on overall comand and we've seen that in his last couple starts. He's not an overpowering guy and has to be pinpoint and mix his pitches better and not cave in in fastball counts. He made a real good showing for himself and worked hard on glove side fastball command."
• Last season, the Cubs set a franchise record in road losses with 56, and this season, they have set a franchise record in most home losses with 50 entering the final game.
"It's so strange how everything is flip flopped from a year ago," Sveum said. "It's disappointing because the fans have been great. To lose 50 games is something you don't really think about at home. It's difficult to take."
• Welington Castillo, who underwent arthroscopic surgery Monday on his right knee to repair a partial tear in his meniscus, was walking around the clubhouse Wednesday, and expected to stay in Chicago for at least two weeks to rehab.
The Cubs catcher, who batted .274 in his first full season as the starter, may continue his rehab at the team's facility in Mesa, Ariz., before returning home to the Dominican Republic.
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings, and you can follow her on Twitter @CarrieMuskat. This story was not subject to the approval of Major League Baseball or its clubs.