BRADENTON, Fla. -- One bullpen session for Josh Shortslef was all that he and the Pirates staff needed to determine that the southpaw's left shoulder is not strong enough for him to continue throwing at this point in the spring.
Shortslef felt some soreness in his left shoulder after throwing on Saturday. It was a red flag for the lefty, who had been feeling an increase in soreness during each of the three throwing sessions he had before arriving at Spring Training.
"It wasn't really bothering me in my long toss or anything, but once I get on the mound, and get some plane on the ball, that's when it begins to get a little tender there in the back of the shoulder," said Shortslef, who spent all of last season as a starter at Double-A Altoona. "It gradually has gotten worse. We don't know what's going on there right now."
Though he has battled injuries in his pitching elbow in the past, this marks the first time Shortslef has ever been bothered by a shoulder ailment. He plans to have an MRI taken on his left shoulder early next week to determine if there is any structural damage.
In the meantime, the 26-year-old lefty has been removed from the list of active participants at Major League spring camp and will not participate in any more Major League Spring Training activities. If he is able to rehabilitate and strengthen his shoulder, Shortslef will report to Minor League camp on Feb. 29.
"It's precautionary," general manager Neal Huntington said of holding Shortslef back. "Rather than push him through and risk injury, we will pull him out of on-field activities and put him through an extensive rehab and throwing program to get him back on the field as quick as we can."
What's up Doc? Damaso Marte is still battling flu-like symptoms and was unable to take part in any of the team's workouts for the third straight day. He remains on antibiotics, though he is still extremely weak and tired.
Olivo Astacio remains limited on his workload after falling behind in his offseason workout plan because of shoulder stiffness and from having to deal with a toothache. He missed his scheduled bullpen session on Sunday, and as of now, there is no specific timetable set as to when he is expected to return to throwing off the mound.
Sights and sounds: Pitching coach Jeff Andrews monitored 17 pitchers throw bullpen sessions on Sunday, as every pitcher who threw on Friday participated in their second side session of camp. Command of fastball and location of pitches were highly emphasized, and each pitcher also practiced pitchouts after throwing his normal 30 to 50 pitches.
On the diamond, fielding drills expanded as pitchers and catchers had their first opportunity of the spring to practice the team's set of signs. Bunting practice, fielding comebackers to the mound and covering first base on ground balls to the right side of the infield were also all practiced on Sunday.
While the pitchers were busy participating in fielding drills, position players already in camp were also taking fielding practice of their own. Both Freddy Sanchez and Doug Mientkiewicz took ground balls at second, while outfielders Kevin Thompson, Nyjer Morgan and Nate McLouth practiced receiving grounders in the outfield.
With Mientkiewicz hopeful of increasing his versatility, he is expected to practice fielding ground balls at a variety of infield and outfield positions throughout the remainder of Spring Training.
More early arrivals: Infielders Ray Olmedo and Luis Rivas have joined the list of early camp arrivals, and both took part in batting and fielding practice on Sunday morning. Both took groundballs at shortstop.
Olmedo, whom the Pirates claimed off waivers on Feb. 1, is in line to compete with Josh Wilson to earn a spot on the Major League roster as the backup middle infielder. Rivas was signed as a Minor League free agent on the same day, with the expectation of giving the organization another experienced infielder for its system.
Bucs bits: Though he was scheduled to come in from Venezuela on Sunday, Carlos Maldonado did not arrive in time to take part in Sunday's workouts. ... The team will have two more days of practice before position players officially begin their workouts on Wednesday.
Jenifer Langosch is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.