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Promotion: Aroldis Chapman

Bryan Smith already did a wonderful job breaking down Aroldis Chapman and his role with the Reds down the stretch, but now let’s examine the fantasy impact of the next big Cuban star.

Chapman, 22, is coming up to pitch out of Dusty Baker‘s bullpen in September, so right off the bat his value is diminished. Very few non-closer relievers are worth carrying on your roster in traditional leagues, unless maybe you’re in a roto league and looking to vulture some wins late in the season. With that said, Chapman could mirror a Hong-Chih Kuo type in the best case scenario; a super-high strikeout lefthanded reliever not limited to LOOGY work (I’m not counting his most recent work as the closer).

I doubt Chapman will be able to match Kuo’s stingy walk rate (2.77 K/9), at least initially; he’s walked 3.6 men per nine innings as a reliever in the minors, 4.9 overall, but it’s worth noting that he’s walked just four in a dozen appearances this month. The rest of the goods are there. He’s death to lefthanders, striking out 53 against just 15 walks with a 51.5% ground ball rate in 32.2 IP in the minors, and good against righties (9.63 K/9 in 66.1 IP). It’s easy to understand why he dominates same-sided batters with his top shelf velocity and slider, not to mention his all arms and legs delivery.

But how useful is he for us fantasy owners? Dusty Baker is than willing to trust young pitchers, which works in Chapman’s favor, but realistically we’re looking at maybe 3-4 innings a week. There’s almost a zero chance of him usurping Francisco Cordero without the help of an injury, and even in that case Nick Masset and Arthur Rhodes are probably first in line to fill-in. If you’re league counts holds, then maybe he’s worth more of a consideration.

Despite the hype, I’d tread carefully with Chapman. The reward is very limited given his role, but the blowup potential is pretty damn big at this point in time. He’s owned in 20% of Yahoo! leagues, but it’s too much of a gamble for me this late in the season. With September right around the corner, it’s a too little, too late for Chapman to have any real fantasy impact.