Samardzija, the former two-sport star at Notre Dame, will stay in the Iowa rotation for now.
"You'd like to think long term," said Oneri Fleita, the Cubs' player development director. "He's like [Carlos] Zambrano when he came up. Zambrano didn't have that second and third pitch, and he developed.
"That's what happens in our game sometimes -- it depends on the needs of the big club sometimes," Fleita said. "The positive is [Samardzija] has versatility at this point in his career, where he could [start or relieve]. Whatever they ask him to do, I'm sure he'll do 100 percent and get the job done."
Samardzija was called up to the big league team July 25 last season and used strictly in relief, compiling a 2.28 ERA in 26 games. He made one relief appearance for Iowa this season, on April 9, and has made two starts since to give him a chance to work on his pitches.
Fleita was in Des Moines, Iowa, when Samardzija faced Round Rock, striking out five over six innings. He walked one and hit two batters, and was slated to start Thursday against Albuquerque.
"The one good thing I can tell you is he has a heck of a future," Fleita said of the right-hander. "Whether it's today or tomorrow, who knows? He's throwing the ball well. I was really pleased with the way he threw the ball."
Fleita also was encouraged by Tyler Colvin's game. The Cubs' 2006 No. 1 Draft pick, who is playing for Class A Daytona, went 3-for-5 on Monday against Dunedin. Colvin is coming back from Tommy John elbow ligament replacement surgery.
"I think Colvin is starting to feel better," Fleita said. "When you're DH'ing, sometimes you don't feel like you're in the game. It sounds like his at-bats have become more consistent."
Marcos Mateo threw four scoreless innings in Daytona's 6-2 win over Dunedin, and may be promoted soon. The Cubs wanted to make sure he was stretched out more before he was promoted to Double-A Tennessee.
In other Minor League news, lefty Jason Waddell has not given up a run this year in four innings over five games, and Chad Fox has not been touched in 5 1/3 innings over five games for Iowa. Teammate Jake Fox, who leads the league in home runs, RBIs, slugging percentage, hits, total bases, and extra-base hits, was named Pacific Coast League Player of the Week. Pitcher Justin Berg, who had appeared in three games, was placed on the disabled list because of a right shoulder impingement.
Carrie Muskat is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.