You might not believe it, but there was a time when Dodgers outfield prospect Joc Pederson was a relatively unknown player. I know it's difficult to imagine given the player he has blossomed into, but Pederson wasn't a high draft pick coming out of high school (11th round in 2010) and didn't become a top-100 prospect until 2013. Though, the Dodgers paid Pederson like a top prospect, handing him the second-highest signing bonus ($600,000) in the team's 2010 draft class to keep him from going to USC.

I had to go back into the archives to see what was being said about Pederson at the beginning of his career to determine just how far he's really come over the last few years. I dug up a scouting report from Baseball America from 2011. They had Pederson ranked as the Dodgers' 25th-best prospect. Here is a snippet from BA's analysis:

"Joc, who was also a wide receiver in high school, doesn't have any dominant tools, but he has the potential to be average across the board and certainly would have gone higher in the draft if not for his price tag. He has a physical, athletic build and the potential to add strength as he matures. … He has a quick bat and average raw power."

The scouting report on Pederson has certainly changed over the last few years. He's now not only one of the top prospects in baseball, but coming into the season Baseball America had labeled Pederson as "a multi-dimensional player whose tools are average to plus across the board, with comparisons ranging from Curtis Granderson to Jim Edmonds."

With Pederson on the doorstep to the majors, his rise from obscurity got me thinking about players right now with relatively low ownership in CBSSports.com leagues that are showing long-term upside. These are players whose ownership are not higher than 3 percent, but names owners in long-term keeper formats might want to put on your radar.

Luis Severino, SP, Yankees
Affiliate: Double-A Trenton
2014 stats (Class A, Double-A): 5-3, 2.50 ERA, 1.07 WHIP, 111 strikeouts, 23 walks and two home runs allowed in 20 starts (97 1/3 innings)
Severino is one of the fastest rising prospects in baseball. MLB.com now has him ranked as the Yankees' top prospect and Baseball America slotted him 34th when they released their Midseason Top 50 list. The 20-year-old right-hander has been pretty dominant in his pro career. He has a 2.23 ERA and 1.04 WHIP in 205 2/3 innings. He is also striking out 9.1 batters and walking just 2.2 per nine innings, and has allowed just five home runs in his career. While his fastball can reach the high 90s, it usually sits in the mid-90s. His slider and changeup are also developing into potential plus pitches. Severino earned an in-season promotion last year and has already earned two in-season promotions this year. He's making a beeline for the Bronx, and hopefully he won't fizzle out like Dellin Betances and Manny Banuelos did once they reached Triple-A. In Betances' defense, he's carved out a niche as an All-Star reliever, but he was once projected to have ace potential, which seems to be the path Severino is headed.

Jake Lamb, 3B, Diamondbacks
Affiliate: Double-A Mobile
2014 stats: .315/.393/.552/.945, five triples, 14 home runs, 35 doubles, 79 RBI, 59 runs, 47 walks and 98 strikeouts in 101 games
I made brief mention of Lamb last week when I was talking about fellow Diamondbacks third-base prospect Brandon Drury. The two are basically neck-and-neck when you look at any prospect rankings for the Arizona organization, but you won't hear the Diamondbacks complaining about being flush with talent at the position. Lamb has done nothing but crush the baseball since turning pro. He has a career .316/.400/.547/.947 slash line in 237 games. Although he was a sixth-round pick in 2012, the Diamondbacks knew Lamb needed work with his swing since he was a slash hitter in college. Well, the Diamondbacks have gotten the 23-year-old infielder to tap into his above-average raw power, while being able to maintain his plate discipline and feel for hitting. The Diamondbacks might have to move Lamb or Drury off the hot corner or trade one, but Lamb has shown great ability to hit in the minors and that's what Fantasy owners want to see.

Steven Matz, SP, Mets
Affiliate: Double-A Binghamton
2014 stats (Class A, Double-A): 8-6, 2.60 ERA, 1.25 WHIP, 99 strikeouts, 30 walks and three home runs allowed in 19 starts (110 2/3 innings)
Matz had a long recovery following Tommy John surgery in 2010, but he's been a great success story coming back from the major elbow injury. He has a 2.49 ERA and 1.20 WHIP over 46 career starts. He is also striking out 9.3 batters per nine innings and has allowed just eight home runs in 246 innings. You can see why the Mets were very patient with the 2009 second-round pick. Matz generates a lot of ground balls thanks to his low-90s fastball and long stride that helps him keep the ball low in the strike zone. Matz has improved his command, which is great because the scouts feel his changeup and curveball could develop into plus pitches. He is showing potential to develop into a No. 2 or No. 3 starter at the major-league level.

Ryan McMahon, 3B, Rockies
Affiliate: Class A Asheville
2014 stats: .278/.349/.484/.833, two triples, 12 home runs, 36 doubles, 83 RBI, 67 runs, 42 walks, 113 strikeouts and five stolen bases in 96 games
The former high school quarterback hasn't looked bad for choosing baseball over football. The 2013 second-round pick has produced a .294/.369/.520/.889 slash line through his first 155 games. He also has 23 home runs, 54 doubles and 135 RBI. He's already an offensive standout and hasn't even progressed past low Class A. Heck, he is just 19-years-old, so it's scary to think what his power potential might be once he grows into his 6-foot-2 frame. McMahon has a fluid left-handed swing and an ability to hit to all fields that allows him to make steady contact. He projects to have plus power and the ability to hit for a high average. It's great that he might one day call Coors Field home. However, the Rockies have a pretty good third baseman in Nolan Arenado, who is expected to remain at the hot corner for years to come. McMahon might have to learn a new position or could end up as a trade candidate, but wherever he lands, this kid seems to have a bright future.

Christian Walker, 1B, Orioles
Affiliate: Triple-A Norfolk
2014 stats (Double-A, Triple-A): .301/.374/.517/.891, two triples, 18 doubles, 22 home runs, 86 RBI, 63 runs, 47 walks, 94 strikeouts and two stolen bases in 107 games
Walker entered 2014 with some scouts doubting his ability to put up big home run numbers. He silenced a lot of those critics when he hit 20 home runs in 95 games prior to his promotion to Triple-A Norfolk. Since moving up to Triple-A, the 2012 fourth-round pick has homered twice and is slugging .524 in 12 games. Walker hit .300 in his first full season as a pro in 2013, and there was little doubt about his ability to make contact. He has been lauded for his gap-to-gap power, but Walker has really taken a step forward this year, which has turned into a breakout performance for the 23-year-old first baseman. Walker has taken a big leap up the prospect rankings, as he is now considered the team's fifth-best prospect by MLB.com. As MLB.com notes: Walker "fits the traditional first-base profile better now than scouts thought he would when he was at South Carolina."

Bonus Player

Austin Voth, SP, Nationals
Affiliate: Class A Potomac
2014 stats (low Class A, high Class A): 6-4, 2.10 ERA, 0.89 WHIP, 114 strikeouts, 29 walks, 67 hits and three home runs allowed in 19 starts (107 1/3 innings)
The 2013 fifth-round pick has been pretty spectacular as a pro. He is 9-4 with a 1.99 ERA and 0.88 WHIP in 30 career starts. He is striking out 9.9 batters and walking 2.0 per nine innings, and he has allowed just three home runs in 153 2/3 innings. Voth's fastball can touch the mid-90s, but he mostly sits in the low-90s. His secondary pitches (changeup, curveball, slider) don't appear to be more than average offerings, but Voth really shines because of his ability to command his pitches. He has an advanced feel for pitching and can work both sides of the plate. Voth said he likes to lean on his fastball and "challenge hitters," per The Washington Post. Well, whatever he is doing is working. He was originally projected as a back-of-the-rotation arm, but he could be developing into much more. He doesn't get hit hard, he doesn't walk a lot of batters and he has a pretty good strikeout rate. If he can keep that up in the high minors, then Voth is a name we might be hearing a lot about in the future.