PHOENIX -- The injury to Padres outfielder Travis Jankowski 's right foot that put him on the 10-day disabled list Monday may be more serious than a deep bone bruise.

Manager Andy Green indicated Thursday before the team's series finale against the D-backs that there is a possibility Jankowski also has a hairline fracture of the tarsal navicular bone in that foot.

"I was told by the doctor there was a serious bone bruise, and the possibility of a hairline fracture. They weren't sure," Green said. "But that doesn't change our approach to how we're handling it."

The Padres are exercising caution, and Jankowski could be out for a month or longer. The outfielder has been with the team this week, but will remain behind at the club's Spring Training facility in nearby Peoria, Ariz., to continue his treatment, while the Padres travel to San Francisco for a three-game series against the Giants starting on Friday night.

"They told me I'd be in the boot for another week to 10 days," Jankowski said. "We'll see how it feels after that, and if we can get anything moving."

When the injury is healed, Jankowski will undergo rehab to rebuild the muscles in the right leg that had atrophied, and then get back into playing shape.

"Yeah, that's going to stink," Jankowski said.

Asked if he was frustrated by the setback coming so early in the season, Jankowski added: "I was frustrated to start, but being frustrated now isn't going to make it heal any faster. I've been talking to Andy a lot just to see how my game can get better, just from the studying aspect of it."

The 25-year-old Jankowski fouled a ball off his foot on April 14, and had been hobbling until he was placed on the disabled list. The left-handed hitter was batting .180 (8-for-50).

"You could see if you were watching closely that it was playing on one foot for the last five to seven games," Green said. "That was partially on me for running him out there."

Jankowski said he wasn't exactly forthcoming about the injury and tried to play through it.

"I mean, I told them what was going on," Jankowski said. "But when they'd ask me, I'd just say, 'I'm feeling good. It's bothering me a little bit, but I'll be able to play in the game.' And it just didn't get better, and that's when we had it evaluated."