Mark Prior's first extended spring start ended prematurely Thursday when the right-hander was forced to leave with shoulder problems.

Cubs general manager Jim Hendry confirmed Prior was removed from the game against minor-league hitters after two innings in Arizona. He declined to comment on the injury until he had more details.
The Cubs said orthopedic specialist Lewis Yocum would examine Prior within the next few days.

Prior experienced discomfort in his right shoulder in the second inning. He left after completing the inning.

Prior was on the disabled list twice with shoulder soreness last season.

He had thrown 75 pitches in a bullpen session earlier this week and was expected to make a five-inning start Thursday to stretch out his arm before his first outing at Triple-A Iowa.

If Thursday had gone well, Prior likely would have been sent to Iowa to start Tuesday. How this latest setback affects Prior's status is unknown, but he likely will remain on the minor-league disabled list.

When Prior was sent to Iowa at the end of spring training, he said he felt good physically and was capable of getting out major-league hitters.

The Cubs have given no timetable for his return to the majors.

But the basic plan called for Prior to rejoin the rotation after two to three minor-league starts, assuming his velocity and control had improved and he was pitching well.

The futures of pitchers Mark Prior and Wade Miller were in doubt on Monday when the Cubs announced Prior would undergo exploratory arthroscopic shoulder surgery and Miller was placed on the disabled list with back spasms.

General manager Jim Hendry said Prior will have his shoulder scoped on Tuesday in Birmingham, Ala., by noted orthopedic surgeon James Andrews. If Andrews has to tighten any shoulder capsules, it's unlikely the right-hander will pitch for the Cubs again this season.

"It's finally got to the point where it's the best decision," Hendry said.

Hendry said he didn't know how long Prior would be out in a worst-case scenario.

"It's a shoulder, and obviously he's going to one of the best in the world," Hendry said. "Hopefully he'll be able to go in there and find something that's not major, and hopefully it helps Mark's career get back on track."

Hendry spoke to Prior over the weekend and said he was in good spirits. When he was demoted to Triple-A Iowa at the end of camp, Prior said he felt fine and could get major-league hitters out. But he left his first extended spring training outing after only two innings, leading to the exams by Dr. Lewis Yocum and Andrews.