Feldman, who signed a one-year contract this offseason, is trying to regain his 2009 form when he won 17 games for the Texas Rangers. Since then he's started just 45 games, compiling a 15-23 record.
Before Thursday the only spots in the rotation that were sure things belonged to Matt Garza, Jeff Samardzija and Edwin Jackson. Feldman was in a group with three others, including Scott Baker, Carlos Villanueva and Travis Wood, battling for the final two spots. Baker is working his way back from Tommy John surgery.
"There's an above average chance Baker is going to probably start a little bit late," Sveum said. "You don't want to rush him or anything like that. ... You have Garza, Samardzija, Jackson, Feldman and those other spots."
Feldman was pleased to hear Sveum's comments but understands there are no guarantees.
"I'm just hoping I can pitch well and hold it down," Feldman said. "Spring training is the time to speculate, but no one knows for sure except the people at the top of the organization."
Feldman threw his first bullpen session on Thursday and said he was at about 80 percent.
"I want to carry it over (to spring games)," Feldman said. "I think I'm a starter, but every pitcher thinks that. I just want to get things rolling. I'm ready to go."
Sveum hinted at the final rotation spot, saying Wood has also looked very good early in spring training while mentioning Villanueva's potential role in the bullpen.