CLEARWATER, Fla. -- The Phillies' bullpen picture came into sharper focus Sunday when right-hander Justin De Fratus and left-hander Jake Diekman were optioned to Triple-A Lehigh Valley.
Left-hander Cesar Jimenez and infielder Josh Fields were also reassigned to Minor League camp.
The organization still has high hopes for De Fratus and Diekman, but pitching coach Rich Dubee outlined what each has to work on.
"De Fratus has to get his arm strength going," Dubee said. "His arm is a little behind right now. His breaking ball is a little too big. He's aware of that.
Diekman's got to learn to pitch backwards. We want him throwing more changeups, use his changeup some to righties. [We] want him using first-pitch breaking balls, breaking balls 1-0 to left-handers and stuff so that people can't start and cheat to his fastball. And, again, command all three [of his pitches]."
De Fratus was on the disabled list with a strained elbow last season, but Dubee said that isn't why he's behind.
"No, I think he just got started a little slower this year for whatever reason," Dubee said. "But he'll be back in the picture soon. He's got plenty of stuff. He's just got to get more reps.
Dubee stressed that both pitchers have bright futures, saying, "Absolutely. They're valuable pieces. Right now they're not there, but they're in the picture for sure. We expect, if we have an injury or something, those guys will definitely be mentioned, for sure."
Said Diekman: "I feel like I'm really close."
The Phillies now have 36 players in camp. If they carry 12 pitchers it appears there are four candidates -- right-handers Phillippe Aumont and Michael Stutes and left-handers Raul Valdes and Jeremy Horst -- competing for three spots.
Aumont flashes his potential against Orioles
CLEARWATER, Fla. -- Right-hander Phillippe Aumont came in to pitch the sixth inning of Sunday's 5-3 win over an Orioles split squad at Bright House Field and walked the first two batters he faced on nine pitches.
Then he struck out the next two hitters and ended the inning with a forceout, demonstrating why the Phillies are so enamored of his potential.
"He was erratic," said pitching coach Rich Dubee. "But it was good to see him grind it out, make an adjustment. He's going to have some rope. You're going to have to give him a leash out there, because he's going to have moments where he's going to lose it for a while. He did it last year when he came up and he did it in this game. He righted the ship where, in the past, he hasn't been able to."
Left-hander Jeremy Horst, who also remains in the running for a bullpen spot, pitched two shutout innings, allowing one hit and striking out two.
"I've seen him better," Dubee said. "But for both him and Phillippe, this wasn't really their day to pitch. They were both going to go [Tuesday, before Jonathan Papelbon got sick and Justin De Fratus was optioned to Triple-A Lehigh Valley]. We kind of jump-started them, so that's fine."
Added manager Charlie Manuel: "We've got guys like Aumont and Horst. We have to get them going, get them sharp. Some of those guys are going to be on our team. We have to get them going for when the season starts."
• Shortstop Jimmy Rollins, who played for Team USA in the World Baseball Classic, is expected to rejoin the team Monday and play in a game at the Minor League Complex.
• Papelbon, who was supposed to pitch Sunday, wasn't feeling well and left Bright House Field before the game started.
• As has become their tradition in recent years, the Phillies wore green jerseys and hats for St. Patrick's Day. The crowd of 11,100 was a Bright House Field record.
• Right-hander Michael Cisco, grandson of former Phillies pitching coach Galen Cisco, was traded to the Angels for no compensation. Between Double-A Reading and Triple-A Lehigh Valley last season, he went 5-3 with a 1.80 ERA in 40 appearances.
Paul Hagen is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.