Marcell Ozuna, MIA - Hit .265 with 3 HRs and 5 SBs over 291 plate appearances for the Miami Marlins. He seems to be one of their building blocks for the future in the Miami outfield. Unfortunately, his season ended in late July to repair a fracture in his left thumb.
Nolan Arenado, COL - Hit .269 with 10Hrs over 503 plate appearances for the Rockies at third base. He has showcased excellent fielding and is probably their third baseman of the future unless they decide to move Arenado to first following Todd Helton's retirement.
Anthony Rendon, WSH - Hit .261 with 7 HRs over 386 plate appearances. He was recalled in April to fill in for the injured Ryan Zimmerman but saw much more action when he replaced the struggling Danny Espinosa at second base. Rendon was considered one of the top prospects in baseball and will most likely keep his spot at second base after being brought up as a third baseman.
Yoervis Medina, SEA - Maintained a 2.96 ERA over 67 innings while serving as a relief pitcher for the Seattle Mariners. Even though he has a very high walk rate, he is a valuable part of the Mariners future and should receive a starting nod in spring training because of his minor league career as a starter and the lack of starting pitching in Seattle.
Oswaldo Arcia, MIN - Hit .251 over 378 plate appearances with 13 HRs. He posses a very strong outfield arm and made two double plays this year from left field. He may end up seeing Twin's prospect Byron Buxton beside him soon, so long as Arcia raises his batting average slightly.
Evan Gattis, ATL - Despite only hitting .238 over 372 plate appearances, Gattis will most likely see increased time at catcher next season even if Brian McCann returns to Atlanta. Gattis provided 20 HRs (projected 31 HRs if Gattis saw a full-time role at catcher) to a team that seems to value power over percentage. A sensation in April, he hasn't seen much attention since because of his low average and McCann's return.
Hyun-Jin Ryu, LAD - A former Korean star made big news in Los Angeles as he maintained a 2.97 ERA over 188 innings as a starter for the Dodgers. Behind Kershaw and Grienke, Ryu is another starter for the future in an amazing Dodger's rotation. He seems to enjoy stardom wherever he pitches because of his vast following.
Jedd Gyorko, SD - A spring training star, Gyorko made his debut under the injury of Logan Forsythe. He hit .249 over 516 plate appearances with 21 HRs at second base for the struggling Padres. A very strong fielder as well, Gyorko simply needs another season to acclimate to major league pitching to raise his batting average.
Alex Wood, ATL - Maintained a 3.16 ERA over 77 innings while serving as a relief pitcher or starting pitcher for the Braves. He started eleven games down the stretch while filling in for an injured Tim Hudson, but a bad September took him out of the rotation. Wood had the third lowest ERA in August for any rookie since 1995.
Brad Miller, SEA - Hit .258 over 327 plate appearances with 6 HRs and 5 SBs as a shortstop for the Mariners. He should see a heavier workload next season because of Brendan Ryan being traded to the Yankees. Miller is a fast prospect and should try to steal more often, evidenced by his six triples.
Zack Wheeler, NYM - Maintained a 3.42 ERA over 100 innings after making his major league debut June 18th. He struggles with command but has a strong status to stat in the major leagues because of the weak Mets rotation. Harvey and Wheeler make up the foundation for a great rotation of the future in New York.
Gerrit Cole, PIT - Pitched to a 3.22 ERA over 117.1 innings in the new Pittsburgh rotation. Only drafted two years ago, Cole sped through the minor leagues to become one of the reasons the Pirates had a winning record and made the playoffs. Jameson Taillon may not be too far behind.
Christian Yelich, MIA - Hit .283 with 10 SBs over 268 plate appearances in Miami. Being the third youngest person in the MLB in 2013, Yelich certainly knew how to hit like a veteran. The only drawbacks with his year was the high number of strikeouts and low power numbers. He also did not commit a single error in the 59 complete games he fielded.
Junior Lake, CHC - A prospect that hit very similarly to Yelich, Lake hit .289 with 6 HRs over 249 plate appearances with the Cubs. He took over a major role when David DeJesus and Alfonso Soriano left via trade. Lake also suffered from striking out too much, but he will become better the more accustomed he gets to major league pitching.
Jarred Cosart, HOU - Started ten games for the Astros to the tune of a 1.95 ERA over 60 innings. His high walk rate and low strikeout rate make his time in the major leagues seem like a fluke though. He was one of the players that arrived in Houston in the Hunter Pence trade and will compete for a spot in the rotation next season.
Danny Salazar, CLE - Maintained a 3.12 ERA over 52 innings while starting ten games for the Indians and certainly helped the Indians keep pace in the wild card race. Salazar had a very high strikeout rate in his rookie season and projects to get 221 strikeouts over an entire season.
Sonny Gray, OAK - Called up July 10th and has been terrific since. Gray has pitched to a 2.90 ERA over 59 innings while making nine starts over eleven appearance for the Athletics. Unlike Jarred Cosart, Gray's low walk rate and high strikeout rate will keep him in the Oakland rotation for a long time.
Juan Lagares, NYM - Hit .247 with 6 SBs over 413 plate appearances. Also one of the best fielding outfielders in the league, Lagares is positioned to start in New York because of the terrible outfield situation for the Mets.
Trevor Rosenthal, STL (RP) 2.63 ERA, 75.1 innings, 108 strikeouts
Jim Henderson, MIL (RP) 2.70 ERA, 60 innings, 75 strikeouts
Seth Maness, STL (RP) 2.35 ERA, 61.1 innings, 35 strikeouts
Brett Oberholtzer, HOU (SP) 2.76 ERA, 71.2 innings, 45 strikeouts
Dane De La Rosa, LAA (RP) 2.88 ERA, 72 innings, 65 strikeouts
Justin Wilson, PIT (RP) 2.08 ERA, 73.2 innings, 59 strikeouts
Adam Warren, NYY (RP) 3.39 ERA, 77 innings, 64 strikeouts
A.J. Ramos, MIA (RP) 3.20 ERA, 78.2 innings, 84 strikeouts
Tony Cingrani, CIN (SP) 2.92 ERA, 104.2 innings, 120 strikeouts
Martin Perez, TEX (SP) 3.55 ERA, 119 innings, 79 strikeouts
Chris Archer, TB (SP) 3.22 ERA, 128.2 innings, 101 strikeouts
Dan Straily, OAK (SP) 3.96 ERA, 152.1 innings, 124 strikeouts
Adam Eaton, ARI (OF) .255/.318/.366, 243 AB
Kole Calhoun, LAA (OF) .281/.344/.464, 192 AB
Scooter Gennett, MIL (2B) .324/.356/.481, 210 AB
Avisail Garcia, CWS (OF) .288/.315/.432, 236 AB
David Lough, KC (OF) .287/.313/.417, 307 AB
Didi Gregorius, ARI (SS) .254/.332/.375, 355 AB
A.J. Pollock, ARI (OF) .269/.322/.410, 439 AB
J.B. Shuck, LAA (OF) .291/.329/.365, 433 AB
For more rookie statistics, see ESPN's rookie batting stats here: http://espn.go.com/mlb/stats/batting/_/position/rookie/sort/WARBR/order/true
*Those rookies with analysis are not necessarily better than the rookies without analysis and are randomly chosen.
**Because of the article's focus, rookies that will receive ROY votes such as Wil Myers, Jose Iglesias, Julio Tehran, Shelby Miller and Yasiel Puig were not highlighted
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