Pederson, Franco headline top prospects called up for September

September roster expansion means MLB debuts for the likes of top prospects Joc Pederson, Maikel Franco and others.

With active rosters having expanded from 25 men to 40 on Monday and the Triple-A regular season at an end, teams are now free to call-up reinforcements from the minor leagues to flesh out their major league roster. Many of those players are those who were on the bubble for most of the season, riding the shuttle between the majors and minors to fill in when major league regulars got hurt or went on leave, or will serve as spot-starters and bullpen reinforcements for an over-extended pitching staff. Among that mass of humanity arriving in big league clubhouses this week, however, are a few of the game's top prospects.

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Mind you, most of this year's most hotly anticipated mid-season major league debuts have already happened, from George Springerin April to Oscar Taverasin May, Gregory Polancoin June, Arismendy Alcantara in July, and Javier Baez and Jorge Soler, bothin August. Others won't happen at all, be it due to injury, poor performance or simply a team opting not to start a player's big league clock simply to play out the string of a losing season. Still, there are four players in particular whose recent promotions make their teams' games that much more compelling. Here's a quick look at that quartet, ranked by the degree of hype that preceded their major league debuts.

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Joc Pederson, CF, Dodgers

Named the 34th-best prospect in baseball prior to the season by Baseball America and the 18th-best in early July (after the promotions of players such as Springer, Taveras and Polanco), the 22-year-old Pederson has had a monster season for the Triple-A Albuquerque Isotopes, hitting .303/.435/.582 with 33 home runs and 30 stolen bases in 121 games, becoming the first Pacific Coast League player to turn in a 30/30 season in 80 years. The reason 30/30 seasons are so rare, of course, is that players that good generally get promoted faster, and there's little doubt that Pederson would have been called up long before Monday if not for the fact that the Dodgers' outfield is already overstuffed with Yasiel Puig, Matt Kemp, Carl Crawford, and Andre Ethier.

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With all four of those veterans under team control through at least 2017, the Dodgers have a serious roster crunch on their hands, and will likely look to make a trade this offseason to make room for Pederson. Exactly how much of an opportunity Pederson gets, however, remains to be seen. The Dodgers are still very much in a divisional race with the Giants, who are just two games behind them, but it's not unfathomable to think that Pederson, who hit ten home runs in August alone, could force his way into the lineup and actually be a key part of L.A.'s defense of the division lead.

The negative view of Pederson is that he's better suited to a corner pasture than center, his stolen bases came at a low success rate (69.8 percent), and he struck out 149 times in those 121 games. On top of that, the PCL, and Albuquerque in particular, is a very favorable environment for hitters. Still, he raked against his fellow lefties this year, hitting .299/.422/.598 in 199 plate appearances, muting another criticism often directed his way, and he has significant upside.

Pederson made his major league debut Monday night as a pinch-hitter with two outs and the bases loaded in the bottom of the ninth inning of a game the Dodgers were trailing 6-3. He worked the count full against Nationals closer Rafael Soriano, but ultimately struck out to end the game.

Maikel Franco, 3B, Phillies

Franco entered this year at No. 17 on BA's prospect list, but fell to 50 by early July amid a lousy Triple-A debut. He picked things up in July and August, however, hitting .324/.344/.580 with 11 home runs over his final 55 games for the Lehigh Valley IronPigs, leading to his call-up on Tuesday. Franco hit 31 home runs in a season split between High-A and Double-A in 2013 and is considered a significant power prospect, and though he won't draw many walks, he doesn't strike out in excess either.

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The big question is whether or not he can stick at third base, where he has good hands but very limited range. Indeed, Franco made 23 appearances at first base (and five at designated hitter) for Lehigh Valley this year. With Ryan Howard and Cody Asche having posted similar .690-ish OPS figures this season (Howard: .225/.308/.383; Asche: .249/.309/.386), Franco is hardly blocked at either corner despite Howard's contract (two years, $60 million remaining) or Asche's youth (at 24, he's just two years older than Franco). But the Phillies would certainly prefer to see Franco make it work at the hot corner, and he should get plenty of opportunities there this month.

Daniel Norris, LHP, Blue Jays

A top prospect after being drafted in the second round in 2011 and signing for $2 million (tied for the fourth-largest signing bonus in Blue Jays history prior to this year), Norris struggled in his professional debut in 2012 and didn't really force his way back onto the prospect lists until this season, when the 21-year-old dominated in 13 starts at High-A to start the year, going 6-0 with a 1.22 ERA, 10.3 strikeouts per nine innings, and a 4.22 strikeout-to-walk ratio. That pushed him to 33rd on Baseball Prospectus' midseason top-50 and 25th on BA's corresponding list.

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He continued to pitch well in Double-A after a mid-June promotion with only a slight hiccup around the All-Star break, during which he threw a perfect inning in the Futures Game for the U.S. team. That success continued in Triple-A after an early-August promotion, as he struck out 23 in his first two starts at that level with his mid-90s fastball/slider/changeup combination. After a poor start last Tuesday, however, he was moved to the bullpen. Indeed, after setting a career high with 124 2/3 innings pitched this season, he is expected to pitch exclusively in relief for the Blue Jays in September alongside fellow 21-year-old rotation prospect Aaron Sanchez, who has posted a 1.66 ERA in that role since being called up in late July. If all goes well, he and Sanchez should be competing for a spot in the big league rotation in March.

Dilson Herrera, 2B, Mets

Herrera was called up on Aug. 29, but we'll include him here as his early promotion was simply the result of incumbent second baseman Daniel Murphy hitting the disabled list with a calf strain. Herrera didn't make any preseason top-100 prospect lists, midseason top-50s or crack the Mets' preseason top-10. But as the key player acquired from the Pirates in last year's Marlon Byrd trade and a 20-year-old middle-infielder who hit .340/.406/.560 in 278 Double-A at-bats in the second half of this season before getting promoted directly to the majors, he's a player worth watching. Herrera is a .297/.365/.460 career hitter in the minors — most of that accomplished as a teenager — and has enough speed and, despite being listed at just 5-foot-10 and 150 pounds, power to post double digits in both home runs and stolen bases. It's also important to note that he cut back on his strikeouts this season, one of many areas in which he showed important growth.

He has thus far started at second base in all four of the Mets' games since his promotion and has fared better in each successive one, going 2-for-4 with a triple and a home run (his first two major league extra-base hits) on Monday and sporting a 4-for-13 (.308) line with two walks against three strikeouts in those four games for a 1.092 OPS. With Murphy eligible for free agency after the 2015 season, a strong month from Herrera in his stead could prompt the Mets to trade the veteran this offseason.