Underwood, the Cubs' second-round pick in 2012 who is coming off a solid season at Class A Myrtle Beach, did not appear in a spring game. Cubs manager Joe Maddon said Monday that part of the problem was that the right-hander had some stiffness in his right elbow.
"A kid like that, the biggest thing for me is to get out there and really develop command of your fastball," Maddon said. "I know he has high velocity numbers and a pretty good breaking ball, too. He has to really learn how to locate his fastball and play off that. If that occurs, a lot of success will follow."
Maddon said they didn't want to rush Underwood, knowing he would open the season in the Minor Leagues.
"When you get a guy that good, that young, you don't push it right now," Maddon said.
Vogelbach, ranked No. 20 among Cubs prospects by MLB.com, was 3-for-14 in six games this spring as the designated hitter.
"He's primarily as advertised offensively," Maddon said. "He uses the whole field. He has power. He's definitely not afraid. He has a nice confident way about him. I thought he had a good camp. He understands what it's all about. It's not that he lacks for self confidence, but he has a better understanding.
"He needs to nail down his defense. As that continues to get better, he'll ascend."
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings. You can follow her on Twitter @CarrieMuskat and listen to her podcast. This story was not subject to the approval of Major League Baseball or its clubs.