Athletic trainer Nick Swartz said Sweeney irritated the cyst when he slid into second base Friday night against Oakland.
"The main restriction was the swelling," Swartz said. "He couldn't bend his knee back."
Berroa had a sprain of the left shoulder, also suffered Friday night when he tried to avoid being hit by a pitch.
After a round in the batting cage Tuesday he said there was just a bit of pain.
"I can handle it," he said.
Bell, quite frankly, said he doubted that the eager Sweeney was 100 percent, either.
"I can't take it from what Mike tells me," Bell said. "I have to see more research than that."
Second opinion: Speaking of medical research, first baseman Doug Mientkiewicz is seeking some this week from back specialist Dr. Robert Watkins in Los Angeles.
Mientkiewicz has been out since July 26 with a lower back problem that has cost him strength in his leg. Bell said the earliest Mientkiewicz would return was after the Sept. 1 roster expansion.
Right-hander Mike Wood, in a rehabilitation start for Triple-A Omaha, gave up two runs on two hits and two walks in three innings of a 4-2 loss to New Orleans. Recovering from a back injury, he'll get another start Friday.
"Health-wise, he says he probably feels as good as he ever did," Swartz said.
A week after elbow surgery, right-hander Brandon Duckworth returned to the clubhouse. He's shut down for about six weeks.
Right-hander Scott Elarton gets his surgically-repaired arm out of a sling in a week. Another righty starter, Adam Bernero, was awaiting MRI and X-ray results on his right elbow.
Left-hander Bobby Madritsch, who had preseason shoulder surgery, has had a setback and won't throw for four to six weeks.
Combined no-hitter: Class A High Desert got its first no-hitter in history when Patrick Green and Jarod Plummer combined for a 2-0 victory Monday over Inland Empire.
Green went 6 2/3 innings for his third win and Plummer the final 2 1/3 innings for his seventh save.
Top form: Luke Hochevar, the No. 1 overall choice in this year's First-Year Player Draft, gave up just one hit in four scoreless innings as Class A Burlington beat Quad Cities, 5-3. Hochevar has not allowed a run in his first six innings as a pro.
Come September: General manager Dayton Moore and Bell held a long discussion on September callups. Moore expects about five to seven players will be summoned from the Minors.
Right-hander Zack Greinke, who's pitched most of the season for Double-A Wichita, is one candidate. He began the season on the disabled list because of psychological concerns.
"We've probably talked about Zack more than anybody," Bell said. "We've had nothing but great reports, both on and off the field."
Omaha reliever Ryan Braun is another possibility.
Up next: The Royals will send left-hander Jorge De La Rosa (1-1, 5.89 ERA), against the Indians' Paul Byrd (8-6, 4.55 ERA), at 7:10 p.m. CT on Wednesday at Kauffman Stadium.