Extra bases

Junior Lake has been "power shagging" during batting practice, which means he's been asked to go after fly balls as if it's a game situation. On Thursday, the Cubs outfielder robbed a player of a home run with a leaping catch at the wall in left. This is just his second season as an outfielder after spending most of his time at either shortstop or third base.

"He's trying to run scenarios over in his head while he's doing plays in batting practice," Cubs manager Rick Renteria said. "As far as we're concerned, he's improving and working to becoming a better outfielder."

Lake also spent some time in the Cubs' Minor League camp, getting extra at-bats this week, and had two hits, including a RBI single, in a 7-0 win Friday over the White Sox.

• The Cubs entered Friday's game with a team on-base percentage of .298, tied for last in the Majors with the Red Sox. However, Renteria likes what he's seen of the players' approaches at the plate, which has produced long at-bats.

"That mentality and that approach is what we've been trying to implement and I think it's starting to happen," Renteria said. "I think over the long haul, once we get into the season and guys are playing on a regular basis and can maintain that approach, hopefully those results will show up in the numbers."

• Outfielder Casper Wells underwent an MRI on his back and was waiting for results. Wells was 1-for-13 in eight games this spring before he was sidelined.

• Barret Loux, 24, whom the Cubs acquired from the Rangers in the Geovany Soto deal in 2012, underwent Tommy John surgery on his right elbow this week in Chicago. The Cubs had originally acquired Jake Brigham for Soto, but there were concerns about his health. Brighman was returned to the Rangers because of an elbow injury, and Loux was then sent to Chicago to complete the deal. At Triple-A Iowa last season, Loux was 4-6 with a 4.84 ERA in 19 games (16 starts).

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.