"I thought Sweeney had a great Spring Training," manager Joe Maddon said. "I'd seen him from the other side, but I didn't realize how good an at-bat he works. I can see him being a very desirable National League player, because he can come off the bench and pinch-hit. That was a tough [decision] for me, because there's a lot going on there that's positive."
Herrera, 30, who batted .300 in 21 Cactus League games, gives the Cubs a backup second baseman and shortstop. He found out his fate on Friday, when Maddon talked to him during batting practice.
"I'm happy to be part of this team," said Herrera, who has played for the Rockies and Red Sox.
The Cubs placed four players on the 15-day disabled list, including Dallas Beeler (right shoulder inflammation), Jacob Turner (right shoulder inflammation), Tsuyoshi Wada (mild left groin strain) and Chris Denorfia (mild left hamstring strain). All players are on the DL retroactive to March 27.
The Cubs kept outfielder Matt Szczur, 25, who batted .362 with five home runs, two doubles and two triples in 21 spring games.
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.