MESA, Ariz. -- Starlin Castro hopes to begin running and hitting off a batting tee Tuesday and said he could be back in Cactus League games by the weekend. However, Cubs manager Rick Renteria was a little more cautious, predicting the shortstop would return next week.
Castro has been sidelined with a mild right hamstring strain suffered March 2.
"It [stinks] to be doing this," Castro said Monday of the rehab. "I'd rather be playing. We'll see this weekend if I'll be in the game."
It's the second straight spring that Castro has missed time because of a hamstring injury. Last year, it was his left hamstring, and the strain was more severe. He's already thinking about what he has to do next offseason.
"I'll just work a little more to get stronger," Castro said.
The plan is to begin baseball activities Tuesday and start taking ground balls Wednesday. Although Castro was eager to be playing by the weekend, Renteria said they'll be careful.
"We want him ready for April," Renteria said.
Samardzija focused on doing his job, not rumors
SCOTTSDALE, Ariz. -- Jeff Samardzija felt he controlled his tempo well, was able to mix his pitches the way he wanted, including his splitter, and took advantage of catcher Eli Whiteside's background with the Giants.
And no matter what he does, the Cubs right-hander's name keeps popping up in trade rumors. Samardzija shrugs them off.
"Just going with the flow, man," Samardzija said after throwing four solid innings Monday against the Giants. "I'm out here pitching, and I'm really excited with how I feel for this season and where I'm at right now.
"I keep getting stronger and I really like how I approached this offseason with spacing it out and not throwing until a little later," he said. "I feel like I'm peaking at the right time. I can't control [rumors]. I"m just going to come out and pitch and keep doing my job and whatever happens will happen."
There were plenty of scouts in the sellout crowd at Scottsdale Stadium. Samardzija's name has been mentioned quite a bit. He'll be a free agent after 2015, and a deal could produce a nice package of prospects for the Cubs.
He's heard the rumors.
"You'd be lying if you said things don't cross your mind like that," Samardzija said. "I'm human, and I have different thoughts throughout the day. Sometimes the uncertainty of the situation pops in my head, for sure. Ultimately, that's just an excuse. I want to go out there and pitch and do my job with no excuses.
"I'm not about to come in and say my mind's shaken because of this or that -- it's not going to happen," he said. "I'm going to go out and do my job. If I win, I win because I did that, and if I don't win, it's because I don't perform up to the task. That's how I look at it. I'm a very practical guy and it's black and white for me. Right now I'm wearing a Cubs uniform and that's how I'm approaching it."
How he approached the Giants was to rely on Whiteside, who played for the team from 2009-12.
"What a good guy to have back there," Samardzija said. "He's won two world championships with them and I think he knows the guys a little. I told him before the game, 'You go ahead and throw down whatever you feel like, and I'll take your word on it.'"
Samardzija scattered five hits, all singles, and did not walk a batter, striking out five. Best of all, he controlled his tempo.
"I really feel like I slowed down out there," he said. "I'm more under control. Me and Lester [Strode, bullpen coach] have talked about that of late. Don't worry so much about the velocity of the pitch but more about how you're throwing it and whether you're selling it to the hitter."
Samardzija was happy not to have to face Barry Bonds, who began a stint as a guest coach with the Giants on Monday.
"I gave up my first hit in the pros to him on this field," Samardzija said. "I opened against the Athletics, and my second game was here and Bonds hit a ball through the hole in the shift and hooked a sinker through. That's one of my earliest memories of being with the Cubs.
"I was happy as heck telling everybody he just got a single off me," Samardzija said.
For the record, Samardzija never faced Bonds in the regular season.
Despite injuries, Sweeney not ready to give up glove
MESA, Ariz. -- Ryan Sweeney says he hasn't thought about switching to the American League so he can be a designated hitter and avoid any more freak injuries in the field.
The Cubs outfielder had to leave Sunday's game because of soreness in his right knee suffered while chasing a ball in right.
"I just slipped and I don't know if it was concrete or a drain or whatever down in the corner, and my front foot slipped and twisted my back knee," Sweeney said. "I felt it pull kind of on the outside and it started to tighten up on me and I kind of got a little scared. They wanted me out of the game to make sure I was OK."
Sweeney had a brace on Monday and hoped to be able to take part in all the drills. After a lot of ice Sunday night, there was still some soreness Monday.
Last year, Sweeney crashed into the outfield wall in Seattle and fractured his ribs.
"It's always the freak things that happen," he said. "Going after a ball in the outfield seems to be the main one. Running after it, you think, 'I'm going to cut this ball off and throw it in.' You don't think you're going to slip. It happens. I should be OK."
So he's not ready to switch and be strictly a DH?
"No, not at all," Sweeney said.
Improving Arrieta eager to face hitters soon
MESA, Ariz. -- Cubs pitcher Jake Arrieta, slowed this spring because of tightness in his right shoulder, threw his second side session Sunday and is continuing to make progress.
"[I'm] spinning everything, everything's sharp, feel great, health's good," Arrieta said Monday. "I recovered today and feel great so far."
The next step for the right-hander is another bullpen session Wednesday of 60 pitches.
"I feel like I'm really close to being ready," Arrieta said. "Building up the endurance and pitch count is something that takes a little more time. We'll see how it goes. Every day has been really good. Still getting stronger. Just refining things is the most important part of the process now."
He'd like to face hitters Wednesday but Cubs manager Rick Renteria took a more conservative approach, saying it will only be a side session.
"We're close," Arrieta said. "We're getting there. I'm excited."
• Mike Olt, who had some soreness in his right shoulder, is continuing to work at third base, and Renteria said the infielder could play there in a Cactus League game soon.
Olt has been able to play first base because the throws put less stress on his shoulder.
"He's building up to [playing third]," Renteria said Monday. "We'll keep going out there and make sure he's progressing and feeling comfortable. I'll say shortly he'll be over there."
• Renteria was a teammate of Bonds in the Minor Leagues with the Pirates. Renteria was a first-round pick in the 1980 First-Year Player Draft; Bonds was the Pirates' No. 1 pick in 1985. They were together at Triple-A Hawaii in 1986.
On Monday, Bonds rejoined the Giants to help coach.
"We played together in Triple-A," Renteria said. "He was up in June and never came back."
Bonds actually made his Major League debut May 30, 1986; Renteria made his Sept. 14 that year.
Renteria was on the Padres' coaching staff when Bonds played his last game in the Major Leagues on Sept. 26, 2007.
"He was always, quite frankly, an excellent baseball player," Renteria said. "My memories of him are that he was an excellent baseball player."
• Outfielder Mitch Maier, a non-roster invitee, has yet to play in a game because of back problems that started right before Cactus League games began. He's been getting a lot of treatment and taking advantage of the new hydrotherapy pool at the Cubs' complex.
"Obviously, it's Spring Training, and I'd rather miss some time in spring instead of the season," Maier said. "I'm hoping for the best and we'll go from there. I've got to get healthy to get on the field."
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.