But those unknowns and long shots can make a difference during the season. Few Phillies fans knew much about infielder Kevin Frandsen, catcher Erik Kratz and left-handers Jeremy Horst and Raul Valdes last offseason, but they helped the Phils at various points. Previously, players like Greg Dobbs, Chris Coste, Mike Stutes and others entered Spring Training relatively unknown, only to play significant roles.
Who are the candidates to surprise and help Philadelphia in 2013?
On Monday, MLB.com looks at the non-roster invitees and newcomers to the 40-man roster on the pitching side. On Wednesday, it will look at the position players.
Here are the pitchers:
LHP Cesar Jimenez: He pitched parts of three seasons with the Mariners (2006, '08 and '11), going 1-2 with a 5.40 ERA in 43 appearances.
"He's an experienced left-hander we're bringing in to compete for a bullpen spot," director of pro scouting Mike Ondo said. "Obviously, Horst and Valdes were pleasant surprises last year and are still with us, but he's another guy to compete."
RHP Ethan Martin: The Phillies acquired Martin from the Dodgers in July as part of the Shane Victorino trade. He is one of the first pitchers mentioned when general manager Ruben Amaro Jr. discusses the organization's top pitching prospects. Martin, 23, went 5-0 with a 3.18 ERA in seven starts with Double-A Reading.
"We obviously liked what we saw scouting him before the [Trade] Deadline," assistant general manager Scott Proefrock said. "He pitched very well when he came over here and put himself on our radar as a guy that has a chance to be one of our starters in Triple-A. And once you get to Triple-A, you never know what can happen."
Martin has little chance to make the club out of Spring Training, but if he continues to progress and a need arises, he could help the Phils at some point (i.e., Tyler Cloyd in 2012).
RHP Zach Miner: He pitched parts of four seasons with the Tigers from 2006-09, going 25-20 with a 4.24 ERA in 157 appearances (35 starts). He is two years removed from Tommy John surgery, going 2-0 with a 2.79 ERA in Detroit's system last year.
New Triple-A Lehigh Valley pitching coach Ray Burris served the same position last season with Erie, which is the Tigers' Double-A affiliate. He gave the Phillies a good report on Miner.
"Before he got hurt, he was pretty successful in the middle innings," Proefrock said. "He could pitch multiple innings with Detroit. Hopefully he's a guy that creates some competition for our younger guys."
Realistically, Philadelphia has Jonathan Papelbon, Mike Adams and Antonio Bastardo as locks for the bullpen. Every other job is up in the air.
"I don't think anybody is assured of anything amongst those other guys," Proefrock said. "He should provide some veteran competition."
RHP Jonathan Pettibone: Following a successful run last season in Reading, Pettibone, 22, went 4-1 with a 2.55 ERA in seven starts with Triple-A Lehigh Valley. Had the Phils not signed right-hander John Lannan to be their fifth starter, Pettibone and Cloyd would have been competing for a spot in the rotation.
"Right now, if we needed another starter, he and Cloyd would probably be the guys that would be first in line, unless we sign some other guys with maybe more experience," Proefrock said. "But he pitched very well last year."
LHP Mauricio Robles: The Phillies claimed the 23-year-old off waivers from the Mariners because they got good reports from their scouts in Venezuela. They like Robles' arm and because the Phils had an open roster spot, they thought they would take a chance.
But the biggest issue with Robles is a sizable one: he has serious trouble finding the strike zone. He has averaged 9.4 strikeouts per nine innings in his five-year Minor League career, but an alarming 5.3 walks. Obviously, if he has any chance at pitching for Philadelphia, he will need to improve drastically.
The Phillies will bring more pitchers into camp, and those announcements could come soon. It would not be a surprise to see right-handers Kyle Simon and Adam Morgan involved. The Phils acquired Simon from the Orioles in the Jim Thome trade in June. He has a good sinker and progressed quickly to Double-A as a reliever.
The Phillies selected Morgan in the third round of the 2011 First-Year Player Draft. Like Martin and Pettibone, Amaro often mentions him as one of the organization's top young arms.