Every year there are rookies that play a big part in October. Matt Moore was a revelation last October, and although there aren't any pitchers of that caliber in this year's rookie class, there are some positional players that could make a huge impact for their squads if they haven't already.
There are others on teams that I believe are on the bubble, so Pirates second baseman Brock Holt and Brewers pitcher Wily Peralta get an honorable mention.
Here are 10 rookies that I believe could make a huge impact come October.
Machado has played a key part since being called up on August 9. He had two home runs on Wednesday against the Blue Jays and continues to be an important piece in the lineup for the Orioles and will be for years to come.
He also has the knack for the big hit, so he could turn into a very clutch performer at the age of 20.
Another Oriole, Bundy has yet to give up his first big league run (albeit in only 1.2 innings). He has yet to turn 20, and Bundy could be a wild card a la Matt Moore from last year.
He will probably be reserved for bullpen work, but as the Cardinals showed last season, a solid bullpen is integral to October success.
As previously mentioned, a solid reliever on the road to the World Series is very important, and Rosenthal has pitched very well in his 16 games in the bigs. With a WHIP of 1.00 and a K/9 over 10, Rosenthal could prove to be very valuable in October.
Another lefty, Maronde has only pitched five innings, but they have been quality innings nonetheless. He has the ability to truly help the Angels if they do make the playoffs, which seems a bit bleak at this time. Weird fact: He is a switch-hitter.
Straily has started six games for the Athletics, some before Brett Anderson returned in August and some recently, including a gem on Monday, giving up a solo home run and striking out eight over 6.2 innings for the no-decision.
Straily might be in the rotation in the playoffs if he continues at this pace, and if not, he is another solid young arm in the 'pen.
Garcia has played his way onto the Tigers scorecard. Since being called up on August 31 he has batted .368. Need I say more?
Well, yes, I do need to. He doesn't have an extra-base hit yet this season, and it isn't as if this 6'4", 240-lb man-child is stealing any bases either.
That being said, he could have a huge impact in the right moments for the Tigers.
Smyly came hot on the scene in April, giving up more than one run only once until May 14. Since then, he has fizzled to the tune of a 4.24 ERA. That being said, the 23-year-old lefty will undoubtedly be an important lefty specialist in the bullpen for Jim Leyland and the Tigers if they maintain their lead in the AL Central.
Having that extra bullpen arm (and lefty to boot) who could also start at a moment's notice is very valuable, especially in October.
Griffin is no secret to any AL team. He seems to be improving as the season grows. He is currently 3-1 in September with a 3.38 ERA. If he can somewhat maintain his 1.05 WHIP, he will be instrumental in the Athletics postseason (if, of course, they make the playoffs).
In case you forgot, Bryce Harper is indeed a rookie. It almost seems like overkill to include him on this list, but he hasn't been as lights out as many had thought when he was selected to the All-Star game. He is batting only .264 but has an impressive 94 runs.
It must be tough for a 19-year-old to play a full season and stay focused, so has Harper gotten a little tired in the dog days? That said, I expect Harper to make a significant impact in October.
Oh yeah, this MVP guy.
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