One of eight rookie pitchers the Cubs have used this season, Samardzija threw on the side Thursday at Wrigley Field to do more tinkering with his mechanics.
"You just keep working," he said. "There are always things you need to improve on. There are always little things you need to fix."
Samardzija made his first Major League start Wednesday, giving up seven runs on eight hits over 3 1/3 innings against the Philadelphia Phillies. The Cubs lost, 12-5, to the defending World Series champs.
Samardzija (1-2), who had appeared in 16 games in relief this year, was making a spot start for injured Carlos Zambrano, on the disabled list with back spasms. The first five Phillies hits off the rookie were all for extra bases. Was he frustrated at the demotion?
"It's been frustrating all around, that's how it is," he said of the Cubs' season. "I'm not mad or anything. It's all about results. You need to go out and get things down. You've got to get outs and get the offense back out there. That's what your role is. I'm a pretty down-to-earth dude. I know what's going on. You've got to make the plays."
That sounds like football player talk.
Samardzija, a former wide receiver at Notre Dame, has shifted from the rotation to the bullpen and back again, beginning in Spring Training, and isn't sure what his role will be down the road.
"The future is the future," he said. "There's still a couple more months left in the season, and we have to figure out what to do this season to help this team down the road. I don't know what's going to happen here in the next few weeks. There's a chance to help this team win -- it's not about the future. I can worry about that in the offseason. I want to come back and help this team win some games."
As a reliever this year, Samardzija compiled a 6.29 ERA in 16 games, giving up 31 hits and walking 12 over 24 1/3 innings. He's learned a lot from both roles.
"I think ultimately, I wouldn't be the pitcher I am now without doing exactly that," he said of switching from starting to relieving and back again. "I think we've made good adjustments now, and now it's just a matter of fine-tuning them."
This is Berg's second stint with the Cubs. He has a 2.33 ERA in 30 relief appearances for Iowa this season, limiting opponents to a .208 average. Since the beginning of June, the right-hander is 5-0 with a 1.72 ERA in 22 appearances.
On Wednesday against the Phillies, Sean Marshall followed Samardzija, and Jimmy Rollins greeted him by launching the lefty's first pitch into the bleachers for a three-run homer. Marshall gave up five runs on six hits over 3 1/3 innings.
"It just stinks to put the team in the hole like that," Marshall said.
On the positive side, Marshall did stay long enough so Lou Piniella didn't overwork his already overworked bullpen. Cubs pitching coach Larry Rothschild had to come out to talk to Marshall during the Phillies' eight-run fourth inning.
"He said, 'Forget whatever happened before this, pitch from here on out, make your pitch and concentrate and try to keep the team in the game,' even though it was already 12-1," Marshall said. "I felt I had a chance to stretch my arm out a little bit, and that was good. It wasn't good to give up so many runs so quickly and put the team in a big hole."
Berg did not appear in a game when he was called up earlier this year. Assuming he gets into a game, he will be the ninth rookie pitcher used by the Cubs. They most recently used nine in 2006: Marshall, David Aardsma, Angel Guzman, Rich Hill, Carlos Marmol, Juan Mateo, Ryan O'Malley, Jae Kuk Ryu and Les Walrond.
Only twice have the Cubs used more than nine rookie pitchers in a single season, and that was in 1958 and 1962, when 10 appeared in games.
Carrie Muskat is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.