Last season, Nelson went 9-for-10 in save situations and held hitters to a .226 average in 43 relief appearances with the Royals.
"It is a question of whether a week was enough time to give it off," Nelson said of his shoulder. "I think it will be. We all go through little things here and there. We'll see if tightness was all it was."
Manager Buddy Bell told Nelson not to rush back in trying to be ready for the first exhibition game Thursday.
"Buddy said, 'I'm well aware of what you are capable of. It is not like I have to build you up to five innings. You're an inning-or-two guy. You'll have plenty of time to get your arm ready again. We're counting on you,' " Nelson said. "That was nice to hear, definitely."
Nelson said it is better to have the sore shoulder in February than in April.
"I don't think a week off is going to kill me," Nelson said. "I've been throwing since Jan. 1. A week off might be a blessing."
Another Elarton bullpen: Scott Elarton, who had shoulder surgery last August, threw 45 pitches in a bullpen session Monday, his third time off the mound in Spring Training. He is scheduled to up his total to 55 pitches Thursday.
"I'm throwing as full as you can get on the side in Spring Training," Elarton said. "I'm not holding anything back at all. Everything is strong. There's no fatigue. I'm hoping I don't have any setbacks."
After six bullpen sessions, Elarton said around March 10 he would throw batting practice. While Elarton will start the season on the disabled list, he remains optimistic he can return to the Major League rotation by early May.
No bullpen duty: Bell said if young right-handers Zack Greinke and Brian Bannister do not make the rotation, they would not likely be kept on the Major League roster as relievers. Greinke made three relief appearances last September after he was called up.
"We want Zack to be a starter and we want Bannister to be a starter," Bell said. "Something crazy would have to happen if they are in the bullpen. I just don't see that happening. We would prefer our younger guys to be in roles that we see them as in the future. Sometimes these young guys will start out in the bullpen and work their way into the rotation, so we're not that set against it, but we would prefer it not to happen.
"Last year was such a fluky situation because we had so many injuries in Spring Training and we broke with guys that we didn't think had a chance to make our club. If it happens, we've got to be ready for that. That could happen."
Two sign: Jose De La Rosa, who was 3-4 with a 5.18 ERA in 10 starts last season with Kansas City, and Carlos Rosa, who was the Royals Minor League Pitcher of the Year in 2006, agreed to one-year contracts Monday.
Six Royals -- Mark Teahen, Ryan Shealy, Bannister, Ken Ray, Joey Gathright and Shane Costa -- don't have deals yet.
Bell to throw: Bell, who had surgery last September to remove a cancerous growth near his left tonsil, said he is feeling great.
"I haven't thrown [batting practice] yet, but I think I'm going to throw BP in the next couple of days and see how that goes," Bell said. "I haven't felt this good in a long time."
With his weight loss, will Bell lose any velocity on his BP fastball? "Actually, it might be a little better," he said with a laugh. "I might have a little more flexibility than I've had in the past."
Open tryout: The Royals will hold a tryout camp on Tuesday with registration at 7:30 a.m. MT at their Surprise complex. Players must bring proof of age, their own equipment and sign a liability waiver. Players under 21 must have a parent or guardian sign the waiver.
Alan Eskew is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.