SURPRISE, Ariz. -- Royals left-hander Bruce Chen still doesn't know if he'll be pitching for China in the World Baseball Classic next month.

At issue is satisfying officials that Chen's grandparents were born in China. They moved to Panama where Chen was born in 1977. He played for Panama in previous Classics, but the team was eliminated in the qualifying round last November. So Chen enlisted with China and practiced with the team three days last week in Peoria, Ariz.

"I don't have any birth certificates from China," Chen said. "I'm giving them everything I can and seeing what I can find. They want me to play, but they want to be sure everything checks out good."

Chen has been working out at the Royals' complex -- he lives nearby -- and wants to get the matter settled soon. Right now, he doesn't know if he's preparing for Classic tournament play or strictly to compete for the Royals' rotation.

"I have to make a decision soon because it's not fair for the Royals, it's not fair for Team China," Chen said.

China opens Classic play in Japan on March 3 against the host country, but has some exhibition games prior to that.

"I have to prepare myself. If I'm going to pitch for China, I have to make sure I'm ready because those games are important," Chen said. "It's not like Spring Training where you're working on stuff to get your arm strong. I already have to have my arm strong."

Meantime, the search for documentation of his grandparents' birth in China continues. Papers to that effect found in Panama apparently are not sufficient.

"They want a direct link," Chen said.

Sherrill hopes to return from injury in April

SURPRISE, Ariz. -- George Sherrill, a left-handed reliever on the comeback trail from Tommy John surgery, believes he will be ready for competition by late April.

"I've been told relievers can come back after about 10 months, but I think it depends on the guy and on the team, that type of thing," he said Sunday at the Royals' camp.

Sherrill was with Seattle when he had the surgery last May and did much of his rehabilitation work with the Mariners. Then he signed a Minor League contract with the Royals as a free agent.

"I got down here and had a week of three days [of throwing] and then all of a sudden, I was just throwing every day. But I've got today off so that's good because it gives me a day to catch up," Sherrill said.

"But the two bullpens have felt great, throwing every day has felt great and from what I'm told, everything in there has healed and now it's just a matter of getting it in shape to go pitch and get guys out."

Sherrill, 35, was an All-Star closer for Baltimore in 2008 and has been very effective pitching to left-handed batters.

"From what they're telling me, if I can be who I was, then I can help out," he said. "So that's what I'm hoping -- to show them that it's just bouncing back and not only does it look good when I'm throwing, it feels good the next day and that type of thing. I don't know, but I don't think I'm even going to throw in a game during the spring."

His bullpen sessions so far have been limited to 15 pitches, all fastballs.

Yost ready to be first at ballpark for physical

SURPRISE, Ariz. -- The first official day of Spring Training for Royals pitchers and catchers on Tuesday will be a busy one. There are physical examinations all morning.

Manager Ned Yost is an early riser and is generally one of the first arrivals at the ballpark. So he'll get the day started. His physical exam comes at 5:45 a.m.