PHOENIX - The three-year hunt for an effective bullpen continues, and it has uncovered Shawn Camp, a 38-year-old righthander who became the 11th reliever used by the Phillies in less than a month. He has joined Jeff Manship, another nonroster invitee in spring training, to form half of the righthanded relief options for manager Ryne Sandberg.

The Phillies entered the weekend with the National League's worst bullpen ERA. They have tried 31 relievers since the start of the 2012 season, and no combination has yielded success. They are ending the first month of 2014 with the sobering reality that, right now, it is difficult to field a seven-man unit that merits a manager's trust.

"Well, it's been talked about," Sandberg said. "It's been addressed. A number of guys have been given the opportunity. That's been the case up until now. A lot of guys have had chances. We're trying to get the right combination and consistency."

They have tried just about every tactic. They signed a big-money closer. Looking for a bargain, they added fringe veterans on palatable contracts. They handed important roles to young arms. Then, when all that failed, they offered $12 million to one of the game's most reliable setup men.

And, still, the same faults lamented by general manager Ruben Amaro Jr. in 2012 and 2013 have emerged in 2014.

The failure extends to the development staff, a unit in which Amaro promised changes last winter. He fired longtime minor-league pitching coordinator Gorm Heimueller and installed Carlos Arroyo, a fixture in the Phillies system, to oversee the pitching progress. New standards for strike-throwing were implemented; a pitcher must demonstrate a certain amount of competency before being promoted to the next level.

The Phillies hoped new voices and perspectives from pitching coach Bob McClure and Arroyo could fix one or two of the arms closest to reaching the big leagues. That, so far, has not happened.

The entire triple-A Lehigh Valley bullpen has major-league experience, and each pitcher is 29 or younger. They are Phillippe Aumont, Justin De Fratus, Luis Garcia, Jeremy Horst, Brad Lincoln, B.J. Rosenberg, and Seth Rosin. Four of those relievers were acquired by trade.

This season, De Fratus, Lincoln, and Rosenberg lasted less than a month in the majors before their demotions. The Phillies developed Mike Stutes, but he was released because of persistent shoulder troubles. Michael Schwimer, a 14th-round draft pick, talked his way out of the organization. Joe Savery never fulfilled his first-round-pick status. The 2009 and 2010 drafts have produced two major-league pitchers - Josh Zeid and Mario Hollands. (Zeid was dealt to Houston in the Hunter Pence trade.)

Hollands, the 6-foot-6 lefthander who emerged from obscurity, is one success story. His first nine innings in the majors were encouraging; scouts like his deception and aggressiveness. But Hollands must prove it over a larger body of work.

Hard-throwing Ken Giles is 23 with limited experience above single A. He could help later. That is why Sandberg said he keeps daily tabs on Giles' progress. The numbers - 21 strikeouts, three walks, and a 0.82 ERA in 11 innings - are eye-popping. But, Sandberg said, it is dangerous to project a reliever based on Eastern League numbers.

For example, the quality of strikes is subjective. Giles can throw a double-A hitter a 101-m.p.h. fastball down the middle that results in a swing and miss. A major-league hitter may not miss that pitch. His slider, which has improved from last season, is a pitch big-league hitters could take for a ball rather than whiff at. Giles, for the most part, pitches in more favorable counts against weaker hitters at double A. What happens when he falls behind in the majors? The Phillies - and rival scouts - expect Giles to handle better competition. The question is when.

Sandberg said the team's reports indicate Giles has improved his command since spring training. Still, the Hall of Famer who spent six seasons as a minor-league manager said it is "hard to gauge" when Giles should arrive.

"How that translates here is yet to be seen," Sandberg said. "The other thing hard to gauge is how much seasoning he needs at the levels to say, 'OK, now he's ready for the next.' There is something about this atmosphere and a young guy maintaining the job he's doing at a lower level. That's experience. There is a time for that and a time to just let the guy have success and be monitored on how he's going about it."

The time for Giles in the majors could be soon. But, as the Phillies have learned, it requires more than one or two or three reliable arms to make a bullpen.

Inside the Phillies: Dry Pen

The Phillies' bullpen ERA and walks per nine innings are among the worst in baseball over the last three seasons. (Statistics are from 2012 through Thursday.)

Worst ERA

Astros 4.74

Rockies 4.37

Mets 4.30

Cubs 4.27

Phillies 4.17

Worst BB/9 inns.

Cubs 4.4

Phillies 4.1

Mariners 3.9

Astros 3.9

White Sox 3.9