Is Starting Aaron Crow a Good Idea?

As Jack Moore covered earlier, the Royals today acquired the services of Jon “The Ox” Broxton. Purportedly, the idea was that adding a reliever was less expensive than finding a starter — which is true — and that they already had a pitcher in the pen that could move to the starting rotation next year — which is more debatable.

The thing is, they might actually have a pitcher in the pen that could start. But it’s probably not Aaron Crow.

Of course, it makes some sense to try Aaron Crow as a starter. He was drafted in 2009 as a starter out of Missouri in the first round, and he started all the way through the minors until he made the bullpen out of spring training last year. In terms of how long ago he was a starter, Crow is the most ‘ready’ to start. That still doesn’t mean that he’s a great option.

After Crow’s success in the pen, it’s tempting to pencil him in for just a little less success in the rotation. He struck out more than a batter per inning, which was good enough to overcome his iffy control (4.5 BB/9) because he enticed more than half of his contact on the ground. SIERA liked him a little more (3.27) than FIP (4.11), but it was a nice season in the pen.

Tom Tango has given us the rule of 17% — strikeout rate decreases by 17% when a reliever moves to the rotation. If we treat the rule as gospel, Crow could manage a 20.3% strikeout rate as a starter. That would go up against an 11.7% walk rate, as Tango also states that walk rate is flat in the move.

If you look for players that struck out around 20%, walked around 10%, and kept about half of their contact on the ground next year, you get some interesting names. Gio Gonzalez (22.8% K, 10.5% BB, 46.7% GB), Derek Holland (19.2%, 8.0%, 46.4%), Ubaldo Jimenez (21.9%, 9.5%, 47.2%) and Ricky Romero (19.4%, 8.7%, 54.7%) provide the nice part of the neighborhood. A.J. Burnett (20.5%, 9.9% and 45.2%) is the warning sign.

It still seems to make sense to move Crow to the rotation. Except that Jeremy Greenhouse also pointed out that velocity changes with a move in roles. He reliably found that pitchers lose about 0.7 MPH when they become a starter. Crow had a 95 MPH heater, which could suffer a mile-per-hour drop and still be fine.

But there are outliers on Greenhouse’s graph. Joba Chamberlain lost about 3 MPH. Phil Hughes lost almost as much. Hong-Chih Kuo and Brett Myers did as well. Scouting reports on Crow coming out of college had him sitting 90-93 with late-fading velocity. His velocity also faded late this past season, sitting more at 93-94 than 95. Will Crow find anywhere near the same success if he sits under 92 MPH as a starter?

His pitching mix is somewhat limited. He uses his fastball and slider about 85% of the time. What happens when he has to use his curveball more? Or his changeup at all? In order to reduce platoon issues and get through the lineup more than once, he may have to use his secondary pitches more. That may not be a good thing.

Crow’s history does not suggest that he will be a good starter, either. In Double-A, Crow struck out only 16.7% of the batters he faced, and still walked 10.9%. He did get groundballs (63.4%), but the strikeout-to-walk ratio negated much of that benefit. Relieving gave him the velocity boost that he needed, and the ability to drop the changeup, which is a fringe pitch at best. Double-A starters with a 4.74 FIP don’t usually make good major league starters.

If Crow is a two-pitch pitcher without a history of success as a starter, is there another reliever the Royals use that might be a better fit in the rotation? What about His Mexcellence, Joakim Soria?

Yes, Soria has less velocity then Crow. If he loses more than 0.7 MPH off of his 91.4 MPH fastball, it may not work. But he has also shown that he can be successful with less velocity. In 2008, his fastball was only coming in at 90.9 MPH, and he had a 3.25 FIP.

Mostly, that’s because Soria is not your typical two-pitch reliever. At different times in his career, he’s used his slider, curveball and changeup more than 10% of the time, and all four of his pitches are above scratch by linear weights pitch type values. He has the arsenal to help him get through the order multiple times.

Of course, this might be going too far. Soria hasn’t started since Triple-A, in 2005, and he wasn’t effective then. And we saw what happened this year when he lost just a little bit off his fastball. Maybe he’s not a great candidate for moving to the rotation.

Then again, is Aaron Crow in the rotation a good idea either? In terms of value to the team, of course it makes sense to at least try, but it doesn’t seem likely to work out.