Ryan Dempster and Kerry Wood are long gone, and a new breed of leaders has emerged in the Cubs clubhouse.

President Theo Epstein cited Anthony Rizzo and Jeff Samardzija as two examples.

"And (Starlin) Castro is showing he's in that group in his own way," Epstein said. "When you play 162 games, that sets a really good example, playing through some nagging injuries, showing up every day.

"I like what some of the veteran pitchers like (Edwin) Jackson and (Carlos) Villanueva have done. Villanueva has been pretty vocal, and Jackson is a really hard worker who is very serious about getting better. And (Alfonso) Soriano, he's very much a leader, very vocal in team meetings, takes young players under his wing.

"It helps them avoid pitfalls and holds them to high standards too. That's something you need in a clubhouse."

Minor matters: The Cubs made a couple of minor league acquisitions, signing infielder Donnie Murphy and outfielder Ryan Sweeney for their Triple-A Iowa roster.

Murphy, 30, is a .205 career hitter over parts of seven major league seasons whom the Brewers released after a spring training invitation.

"Kind of (a) hard-nosed utility type of player who is going to catch the ball wherever he plays," Sveum said. "He doesn't have a whole lot of at-bats in his short time in the big leagues. He did swing the bat OK in the minor leagues when he was there. Strikes out a little too much for that role, but a guy you can rely on defensively and a little 'gamer' type of guy."