I identified 27 starters on contending teams that have ERAs outperforming their FIP up to this point in the season. And please don't misinterpret what I'm saying -- I'm not suggesting that they absolutely will regress to their FIP, because that is unlikely to happen unless they perform very, very poorly in their remaining starts.

What I'm saying is this -- what does their FIP say concerning the level they are likely to perform at, if they continue to pitch the way they have been? And which teams are the most at risk of stinging performances by their starters?

For example, Hiroki Kuroda of the New York Yankees is currently sporting a 2.45 ERA but his FIP is 3.34. While his ERA outperforms his FIP by 0.89, I wouldn't necessarily consider him, or the Yankees, in trouble as a result of that. Same thing for a guy like Clayton Kershaw who has a 1.91 ERA but has a FIP of 2.47, and if he were to perform at that level the rest of the way the Dodgers would be thrilled.

There are three teams that I have identified as having to face the biggest hurdles when it comes to regression by certain members of their starting rotation while trying to reach the postseason.

Oakland Athletics

Why are the Athletics in a position where they should be concerned?

The reason is simple; they had a three and a half game lead over the Texas Rangers in the American League West on August 1 but because the pitching staff has performed so poorly as of late they are now tied. Secondly, they have four members of their rotation on the list that could potentially (there's that word again) perform worse the rest of the season than they have up to this point.

Player	ERA	FIP	Difference
Bartolo Colon	2.75	3.41	0.66
Tommy Milone	4.39	4.48	0.09
A.J. Griffin	3.91	4.61	0.70
Jarrod Parker	4.02	4.63	0.61

Now, the possible regression for Colon isn't all that terrible at all on its own but it's when you look at the numbers for the other three members of the A's rotation when things begin to get a bit concerning. There's a total difference of 2.06 runs between the ERA and FIP and that's going to add up quickly over each of these starters nine or so remaining starts.

Kansas City Royals

The Royals are in a unique position. They play in a weak division but the front runner in the division, the Detroit Tigers, continue to play excellent baseball as the season wears on and any reasonable person shouldn't expect the Royals to make up eight and a half games against them. However, they have a punchers chance at a wild-card spot, sitting just four and a half back there, but the one area they tried to address the most in the off-season is likely to hold them back.

Player	ERA	FIP	Difference
Ervin Santana	2.97	3.66	0.69
James Shields	3.36	3.88	0.52
Jeremy Guthrie	3.96	5.11	1.15

Santana and Shields have been great for the team, especially Santana, but they are unlikely to keep that up as we get into the portion of the season that often times carries the most importance in regards to wins and losses. Guthrie is looking far worse and unless Danny Duffy can regain his command, thus improving his ability to go deeper in games, the Royals don't have any other serious options to replace Guthrie if he does in fact struggle.

Baltimore Orioles

Oh, my dear Orioles -- how you have the potential to make us weep.

Being just a game and a half back of the wild-card and five and a half back of the American League East lead is mighty impressive when you consider manager Buck Showalter has already started 14 different pitchers this season.

Player	ERA	FIP	Difference
Miguel Gonzalez	3.91	4.38	0.47
Chris Tillman	3.89	4.84	0.95

It makes sense that the two starters in the Birds rotation looking to be due some regression are also the two that seem to give up the long ball more often than not, Tillman having given up 23 so far and Gonzalez 17. For a team that's not especially deep in, quality, starting pitching if these two aren't as fortunate down the stretch or don't figure out a way to reverse the direction they seem to be headed in then the Orioles playoff hopes will suffer.

. . .

All statistics courtesy of FanGraphs.

Lance Rinker is a writer at Beyond The Box Score. You can follow him on Twitter at @BSLLanceRinker.

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