It's no secret that Cole Hamels has pitched poorly of late. Over his last two starts his ERA is 19.89 and over his last seven starts, going back to June 8th, it sits at 6.10. The peripheral stats indicate a better pitcher as Hamels's respective FIPs over those stretches are 4.48 and 2.49. Nevertheless, the poor surface numbers have caused a good bit of hand-wringing as the trade deadline approaches and the Phillies hope to maximize their return for their ace.
But should teams actually be concerned that Hamels's poor recent performance indicates that something is wrong? The first indication that Hamels's struggles reflect some underlying injury would be a decline in velocity. Below is a graph of the velocities of each of his pitches in each start, via Brooks Baseball:
Aside from his Sunday start, a day game where the temperature was 93 degrees, Hamels's velocity has been generally consistent throughout the year. You will notice a bit of a drop seven starts ago--the publicly accepted beginning of his struggles--but it rebounds over the course of the following two or three starts to his normal levels. That drop might have caused his poor results Sunday and on June 8th against Cincinnati, but I'm not convinced it explains the larger decline fans fear.
Starts | O-Swing% | Z-Swing% | Swing% | O-Contact% | Z-Contact% | SwStr% |
First 17 | 34.4% | 70.3% | 50.6% | 55.4% | 83.9% | 13.4% |
Last 2 | 37.2% | 76.5% | 53.7% | 68.6% | 94.2% | 8.5% |
It's just two starts, so we're not going to draw any strong conclusions from this, but, in general, opposing hitters are swinging more at Hamels's pitches and making contact on more of those swings, both in and out of the strikezone. In his last two starts, opponents are making contact on 94.2% of the pitches Cole throws in the zone that they swing at. For reference, Sean O'Sullivan, a pitcher with substantially worse stuff than Hamels, has a career opponents Z-Contact% of 93.1%.
In short, all these splits indicate that Hamels's stuff has been worse over his last two starts as hitters are better able to connect on his pitches.
Let's expand the scope to his last 7 starts to see if these splits remain:
Starts | O-Swing% | Z-Swing% | Swing% | O-Contact% | Z-Contact% | SwStr% |
First 12 | 34.0% | 69.5% | 50.5% | 54.6% | 85.1% | 12.9% |
Last 7 | 35.6% | 73.2% | 51.6% | 59.7% | 84.0% | 13.1% |
6/8 - 7/5 | 35.2% | 72.3% | 51.0% | 56.9% | 80.8% | 14.5% |
If we just look at Cole's 7 most recent starts, there is some cause for concern as the trends of batters swinging more and making more contact against Hamels generally shows up in those splits, albeit to a lesser extent. However, if you take out Hamels's two most recent starts, Hamels looks like Cole Hamels looked through early June--like a front-line starting pitcher. I think it is justifiable to exclude his two most recent starts as outliers. His July 10th start against the Giants was the worst of his career and his Sunday start against the Marlins was on an unusually hot, 93-degree afternoon.
Smart money is on Hamels returning to form when he next takes the mound, if he's still with the Phillies, against the Chicago Cubs this weekend. Let's be clear, as Fangraphs's Eno Sarris was yesterday, that Hamels's default form these days is that of one of the ten best pitchers in baseball.
These two most recent starts, or even this last 6 weeks of mediocre results, should not cause the Phillies to alter their demands in trade. They should still demand at least one difference-making prospect in return for Hamels because Hamels is a very fairly-paid difference-making pitcher. As John Stolnis pointed out prior to Cole's implosion against the Giants, the only reason to trade Cole is if the return changes the direction of the franchise. Nothing in his recent performance indicates that the Phillies should move into sell-low mode.