MESA, Ariz. -- Cubs pitcher Jake Arrieta is inching closer to throwing off the mound.
The right-hander, projected as one of the club's starters, has been slowed this spring because of tightness in his right shoulder. He will have a flat-ground session on Saturday, and the Cubs will decide if he's ready to take that next step and get on the mound after that.
"We're going to take it day by day," Arrieta said Friday. "Every day's been good. It's gotten progressively better. If we stay on the same schedule, I'm optimistic I'll be ready by Opening Day."
Arrieta has competition for the rotation. The Cubs signed free agents Jason Hammel and James McDonald and also have lefty Chris Rusin in the mix.
Schierholtz sent home following outfield collision
MESA, Ariz. -- The Cubs' Nate Schierholtz was sent home as a precautionary measure after a collision in the outfield with Junior Lake during a drill on Friday.
Cubs manager Rick Renteria said Schierholtz checked out fine and should be back on Saturday.
The Cubs were doing fly-ball drills when the accident happened in shallow right field.
"They were both calling for [the ball], and it sounds like Junior might have gotten him with the back side," Renteria said. "You're talking about two strong men."
Lake converted to outfield late last season, having spent most of his career at third base.
Baez shatters car window with home run
MESA, Ariz. -- The Cubs need a few more signs at their new Spring Training facility to warn fans of Javier Baez's power.
Baez apparently broke a car window with one of his batting-practice home runs on Friday.
"I saw it fly and I heard a sound," said infielder Logan Watkins, who was in the outfield during batting practice.
What did he hear?
"Glass," Watkins said.
"Somebody told me, but I didn't know that," Baez said about the freak accident. "It [stinks] for the person who parked there."
This is the Cubs' first spring at the new facility in west Mesa, and there are a few glitches.
"They're parking too close to the field," Baez said.
It's not just Baez either. Jorge Soler launched a ball out of Field 5 as well. Maybe they need more screens? Or park farther away?
"[At least] not until Group 1 is done hitting," Watkins said. "Mike Olt hit a couple far out there, too."
Home runs are not unusual for Baez, 21, who belted 37 combined at Class A Daytona and Double-A Tennessee last season. This is Baez's second year in the big league spring camp, and he said it's a little easier.
"I'm trying to follow all the big guys," the shortstop said.
Starlin Castro has been encouraging Baez, who is challenging for Castro's job.
"[Castro] tells me all the time, 'You're going to get there whenever they think you're ready,'" Baez said. "We're just waiting now."
Third baseman Christian Villanueva, who also was in the outfield during batting practice, gave Baez a description of what happened in Spanish.
"It was impressive," Villanueva said. "I think he hit two cars. Some family was getting into the car and they heard the noise. They're like, 'Who's hitting?'"
Baez didn't know what happened.
"He doesn't even care," Watkins said. "He's like, 'Oh, cool.' It's not cool for whoever's car it was.
"That's a fun group to watch hit. They were making that field look real small. I get in trouble if I try to do that because that's not really my game. Last round, I try to put one over [the fence] at least. He can do it every round if he wants. I don't think anyone's going to say, 'That's not your game,' because it obviously is."
Kalish marvels at US women's hockey team
MESA, Ariz. -- Ryan Kalish felt nearly as bad as the U.S. women's hockey team after it lost to Canada in the finals of the Winter Olympics on Thursday. Kalish, a non-roster invitee in Cubs camp, trained with some of the U.S. women a year ago.
"They were fun to be around," Kalish said Friday. "These women, they train so hard for their sport and they don't get paid any money. It's all about passion. Obviously, I'm very passionate about baseball and there's big money in it, so it's a lot more appealing [for me]. They're working for every four years.
"They were so ready to go every day, early mornings, trying to push themselves, lifting weights, running, the whole nine," the outfielder said. "And that was only the beginning of their day because they had [hockey] practice later."
Kalish, who was with the Red Sox organization prior to signing with the Cubs in December, worked out with the women at Mike Boyle Strength and Conditioning near Boston. Boyle is a consultant to the Red Sox and designed a program for the women's hockey team.
"[Boyle] loves hockey, so he did a lot of the training for free out of the kindness of his heart," Kalish said. "It was so cool to be around them. They're working for a medal, for the love of the game. Being around that was awesome for me.
"Their passion was just inspiring," he said.
• Jeff Samardzija is expected to start the Cubs' Cactus League opener Thursday against the D-backs in the first game at the team's new Spring Training stadium, Cubs Park.
Renteria did not reveal the rest of his spring rotation. The Cubs will tune up for Cactus League play with an intrasquad game on Wednesday at the new stadium. Top prospects Eric Jokisch and Kyle Hendricks will start that game.
• James McDonald was happy with his live batting-practice session on Friday. It's the first time the right-hander has faced a batter in about 10 months.
"This is the first time I was throwing without thinking about my arm in a while," said McDonald, who was limited to six games with the Pirates last season because of shoulder issues. "I was like, 'OK, my arm feels good.' It was fun to be able to get out there and throw off the mound to a hitter."
His goal, besides staying healthy, is to be better at the end of spring than he was on Friday.
"A lot of times when you first see a batter, you speed up," McDonald said. "You get a couple times out and you start relaxing and you're good. The first time out, seeing batters in a while, I feel like I got a little [rushed]."
• The Cubs will be featured in three live Spring Training games on MLB Network, and the games will be available in the Chicago area. Those dates include March 12 against the Mariners at 9 p.m. CT, March 18 against the Rangers at 9 p.m., and March 19 against the Rockies at 8:30 p.m.
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.