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Bearish on Ryan Dempster

This is part of an ongoing pro/con series on RotoGraphs over the next couple of weeks. Today we’ll look at the positive/negative side of Ryan Dempster. Expect the opposite side shortly.

It would be easy to look at Ryan Dempster‘s 5.48 ERA and 1.41 WHIP, his solid work the previous three seasons, and conclude that one should be bullish on his prospects moving forward. After all, his BABIP is an inflated .320, his HR/FB ratio is a career high 15.5% and his LOB% is well below the league average. But that would be too easy and I like challenges.

First off, I am not going to try to argue that Dempster won’t see better fortunes ahead. So no, he will not finish with an ERA above 5.00. But fantasy owners likely paid for a mid-to-high 3.00 ERA, so a mark above 4.00 would still be rather disappointing. And I think that is a distinct possibility, despite a rather strong 89 xFIP- and 3.31 xFIP.

Dempster has posted peripherals very much in line with previous years, including a strikeout rate that ranks second highest during his seasons as a full-time starter. However, I have discussed here in the past how K/9 could be affected by good or bad fortune in our luck metrics. A high BABIP means more batters faced during an inning, and therefore more opportunity for strikeouts. Dempster’s K/9 ranks 19th among pitchers with a minimum of 50 innings pitched, while his K/PA ranks a less impressive 29th. Though he may look forward to better luck ahead, that could very well be offset by a drop in strikeout rate.

Possibly more troubling is his SwStk% and Contact%. His SwStk% mark has not fallen below 10% since 2003, when it was still an above league average 9.7%. Likewise, his Contact% has always been strong, never rising above the 77.6% mark he also posted in 2003. This year, however, his SwStk% is down dramatically to just 8.5% (versus 10.9% last year), while his Contact% has jumped to 81.0% (versus 75.0% last season). Usually when this happens, a corresponding decline in strikeout rate occurs as well. But I think the bad luck has inflated his apparent strikeout ability so far.

Last, his velocity is currently sitting at 90.2 miles per hour. Last year, he was averaging 91.0 miles per hour with his fastball. Now, 0.8 miles per hour is not that significant, but it is worth nothing that this is still the lowest average speed he has ever experienced. In addition, he has induced the highest O-Swing% of his career. Normally, this would be a good sign as pitches outside the strike zone are obviously more difficult to make contact with and hit hard. Unfortunately, he has also easily allowed his highest O-Contact% as well (previous career high of 55.7%, this year 68.2%, right at the league average). So hitters are swinging more at pitches outside the zone and also making more contact. That contact may very well be weak contact (though his BABIP would suggest otherwise), but that may also simply mean his slider has had less bite (rings the cliché bell!) than it has in the past.

I do think Dempster will improve, but something still just doesn’t seem right once we get past the obvious bad fortune we immediately detect from our luck metrics.