On Saturday, I checked in on the National League starting pitchers whose SwStk% suggests a strikeout rate surge may be coming next season. Today, I will identify the pitchers whose SwStk% suggests the opposite side of the coin, those whose strikeout rate may be in for a decline next year. As a reminder, the league average is a 7.3 K/9 and 8.6% SwStk%.

Ryan Vogelsong | 7.1% SwStk% | 7.4 K/9

Though Vogelsong’s luck finally disappeared in August in September as he posted ERAs above 6.00 during both months, he has still outperformed his SIERA for the second season in a row. And, his SwStk% suggests that his strikeout rate should not be at this high a level. Though his K/9 is just about at the league average, his SwStk% is 1.5% below that average. He was posting similar SwStk% marks while with the Pirates from 2003-2006, yet never posted a strikeout rate above 6.4.

So without the ability to make batters swing and miss, I am not exactly sure how he is managing to strike batters out at the rate he has been so far with the Giants. His poor finish will ensure he isn’t dramatically overvalued in fantasy leagues next year, but he still remains a pitcher I want no part of no matter what the league depth is. The upside is limited and downside too great, with a solid chance he is worthless in even deeper mixed leagues.

Yovani Gallardo | 7.8% SwStk% | 9.0 K/9

On the surface, Yovani is having just another typical Gallardo type season. A deeper look though reveals that he had never posted a SwStk% below 8.4 previously. It’s hard to believe that a huge strikeout pitcher like Gallardo would be nearly a full percentage point below the league average in inducing swinging strikes. Now, he has never posted gaudy SwStk% numbers, so it is safe to say he must get more called strikes or induce more foul balls than the average starter. However, that would seem to only boost his strikeout rate into the mid-to-high 7.0 range.

His average fastball velocity is also down 0.9 miles per hour from last year. Like with any of the pitchers on these lists, it is important to understand that any strikeout rate decline expectation is based on all else equal, means a similar SwStk% next year. It is possible, and perhaps likely, that Gallardo’s SwStk% does rebound next year. That said, there are enough red flags between that metric and the velocity decline that he’s one to shy away from paying full value for.

Mike Fiers | 8.1% SwStk% | 9.2 K/9

With another 10 strikeouts in just 6 innings yesterday, Fiers’ strikeout rate actually sits at 9.5 now. Pretty amazing for a guy who managed just an 8.0 mark at Triple-A this year and only averages 88.0 miles per hour with his fastball. I have no idea how he’s doing it though. His SwStk% is below the league average, yet his strikeout rate now ranks second in the National League. Does he get a ton of called strikes? If StatCorner still had that statistic, I could check, but alas, they removed it for some reason.

I have to think it’s been a lot of luck with his sequencing, which is exactly what would lead to an expectation of regression the following season. Given that he’s already 26 years old and ranked just 15th among the Brewers top 15 prospects in the pre-season, he might not even be overvalued in fantasy leagues next year. He’ll be a difficult one to project though, but it may not cost a whole lot to take the gamble.