Reader mail! I like reader mail. Sam Coatham from Hampshire (not the place I went to college, but the England one) writes:

Tyson Ross doesn't appear to be good enough for the majors at the moment, is that just a couple of bad starts, or is he simply not good enough?

If he is demoted, who would you replace him with? Is Peacock ready?

Ross's turn in the rotation is up tomorrow (Monday), as he's due to face Dan Haren in Anaheim. The matchup wouldn't favor Ross on his best day, although one should note that the Angels have scored even fewer runs than the A's on the season, so it's not like Ross is heading out to get knocked around by Texas.

Let's start with the basic number first: Ross has thrown 25 2/3 innings over five starts (not an impressive number of innings per start), facing 120 batters. He's struck out 13 of them, handed out 12 free passes (11 walks and one HBP), and allowed two homers. The hits have been falling in, as he's given up a .366 BABIP. All of this adds up to a terrible 22 runs allowed.

If we can find a positive, it's that his ground-ball rate, per Baseball Prospectus is at 58%, which is even higher than his 2010 rate of 55%.

The immediate concern with Ross's numbers is that it looks like he's doing two things, rooted in one problem: he's failing to throw strikes, and he's failing to throw quality strikes when he does throw strikes. If you can't hit the zone, you give up walks, and if your pitches are grooved when you do hit the zone, you give up hard-hit balls and you don't miss bats, leading to few strikeouts.

We can look at some PITCHf/x data to see how much of this result-stats stuff bears out. First, compare how Ross pitches lefties and righties vs. the league averages:

Ross pitches v. LHB	League v. LHB

Ross pitches v. RHB	League v. RHB

The alarming thing is how many of Ross's pitches are ending up in the middle of the zone to righties. He's trying to get to that outer half of the plate, the way all pitchers do, but he does not appear to be succeeding. That said, lefties are the ones doing the damage against him, hitting .383/.473/.532 so far.

I'm not going to post image after image here, because as I click around the TruMedia site, filtering on pitch type, batter handedness, etc. etc., I don't see any single problem. What I do see is everything Ross throws being contacted: his whiff percentage (misses divided by swings) of 15.8% is just right around the cutoff for the bottom 10% in the league (>=200 pitches thrown). Neither his changeup nor his slider has induced whiffs at a higher rate than average, although the slider, at least, is close.

After staring at this data for a long time, I came to realize that I'm probably making this harder than I need to. Ross was drafted in 2008 in the second round and given just under $700,000 to sign. Baseball America immediately rated him the 15th-best prospect in the A's system, and bumped him to 6th and 4th in its 2010 and 2011 books. They said he had the best slider in the system in each of those years as well. You may be surprised to hear, then, that in Ross's nine stops in professional baseball (not counting a rehab stint last year), he's pitched well in exactly three of them.

PECOTA took all this data and spat out a replacement-level projection for him: zero WARP in 81 2/3 innings. ZiPS was even less optimistic, seeing an ERA over half a run higher, down in Fabio Castro territory.

What about Ross's mechanics? Here's a picture of Tyson Ross's release points for each of his fastballs in order for 2012:

That doesn't look terribly consistent. It's hard to know without having a full PITCHf/x database whether it really is bad, though. The standard deviation on Ross's horizontal release point is about 2.2 inches, while on the vertical it's about 1.6 inches. Looking at this article by Mike Fast, you can see lists of high and low standard deviations for pitcher fastballs. The problem for me is that Fast just uses one number, and I don't understand what that number is, so I don't know how to compare these results to the tables in that article. Further, that's the only article I've found that has any lists of data on release point consistency, so I don't know where else to compare these Ross findings.

Has any of this led to any conclusion yet? I'm not sure, but I will say that none of it is terribly positive. Ross has velocity and his sinker has good movement, with occasional Cahill-like flashes, but it isn't clear to me that he's a major-league starter if he can't manage his arm and his body to the point where he can throw the ball where he wants to throw it, or at least within a reasonable radius of that spot.

The second half of Sam's question is harder, if that's possible, because all I have on the A's minor-league pitchers are stats and the opinions/reports of all the same people that you, dear readers, have access to -- the Kevin Goldsteins and Keith Laws of the world, that is. It does not appear that the former has written about Peacock since the season started, so we're left with what we already know (mid-rotation type with plus velocity, but known as a control type) combined with his Sacramento line: 39 1/3 innings, 37 strikeouts, 14 walks, 2 homers.

When you look at that line and you examine the alternatives (Graham Godfrey on the 40-man, Travis Banwart, Fabio Castro, or Bruce Billings (yes, he's working as a starter in AAA) off of it), I wouldn't be surprised to see Peacock up by mid-year if Ross continues to struggle and Dallas Braden isn't ready to come back by the time the A's are ready for a demotion. That said, as fun as this team has been so far, the question for Billy Beane is almost certainly about Peacock's development first and foremost, not about which pitcher gives the A's the best chance to win in 2012. If Peacock reaches the point where it's time for him to face new challenges, then I think he'll come up whether Ross is pitching mediocre or poorly. (If he's pitching quite well, which I doubt he'll do, then it creates a stickier problem, but let no fan complain about having too many good players.)