This is a statistical snapshot of  the Royals rotation prior to James Shields’s disaster start on Tuesday.

1 SP Jeremy Guthrie 3.69 17 17 0 112.1 110 48 46 16 27 68 469 111 4.67 1.220 8.8 1.3 2.2 5.4 2.52
2 SP Jason Vargas* 3.53 17 17 0 112.1 115 45 44 14 25 74 469 116 4.20 1.246 9.2 1.1 2.0 5.9 2.96
3 SP James Shields 3.79 17 17 0 111.2 120 58 47 15 24 87 476 108 4.12 1.290 9.7 1.2 1.9 7.0 3.63
4 SP Yordano Ventura 3.26 15 15 0 88.1 87 33 32 7 25 76 372 125 3.29 1.268 8.9 0.7 2.5 7.7 3.04
5 SP Danny Duffy* 2.60 17 11 1 72.2 49 23 21 5 29 55 294 157 3.80 1.073 6.1 0.6 3.6 6.8 1.90
Provided by View Original Table
Generated 7/1/2014.

The symmetry of the top three starters is kind of cool. Seventeen starts for each, they are within two-thirds of an inning and they are within seven batters faced.

What causes some concern is the ERA column followed by the FIP column a little further down the line. Entering Tuesday, all three were outperforming their FIP. Guthrie has been outpacing his FIP and xFIP for his entire career. Last year, the difference between his FIP and ERA was 0.75 and that was good for a 1.1 fWAR. This year, the difference is nearly a full run and at the halfway point, his fWAR is 0.5. Vargas is usually a little closer. Shields’s FIP is his highest since 2010. Not coincidentally, that was his worst season as a starter.

This is three-fifths of the rotation. These are the guys making the serious cash. And they look to be walking the tightrope.

Shields has been miserable his last nine starts. In his last nine starts, he has a 5.43 ERA covering 56.1 innings. During that time, he’s struck out 36, walked 14 and surrendered 10 home runs. Opponents are hitting .323/.362/.557. He doesn’t look hurt or mechanically broken. He’s just hittable.

If you revisit the chart above, Guthrie and Vargas are exactly the same pitcher, statistically speaking. And it looks like both will regress. ZIPS has Guthrie throwing 88 more innings this year with a 4.64 ERA. It has Vargas down for 98 innings and a 4.55 ERA. Obviously, these are projections so they have to be taken as such, but those numbers are frightening. At this point, the best thing we can say about Guthrie and Vargas is they have kept their team in games when they make starts. That’s not meant to be some kind of backhanded compliment. It’s fact. These two are going out there knowing their offense isn’t going to give them a ton of runs, and they grind out their appearances. The Royals have won 19 of their 34 starts. That’s a .559 winning percentage. That gets you into first place in the AL East.

The projection on Shields is more positive. ZIPS has him down for 106 innings and a 3.83 ERA.

Any time we gaze into the crystal ball, we really don’t know what’s going to happen. This isn’t meant to be a negative type of post where I’m spreading gloom and doom. Shields could find his change-up magic and Guthrie and Vargas could beat the projections all season, just like they have so far. That would be nice, wouldn’t it? Or everyone could go off the rails. Hell, if anyone missed time due to injury, the whole thing could fall to shambles as there’s no major league depth in the organization right now.

The point is, Shields is scuffling and Vargas and Guthrie are way outperforming their peripherals. The Royals really need Shields to get it together if they are going to make any kind of run at October. Because to count on the rest of this rotation to continue to be this great would be risky.