Potential NL SP Strikeout Rate Surgers

On Wednesday, I compared American League starting pitchers’ strikeout rates and SwStk% marks to determine who may be in line for a K/9 surge next season. Today I perform the same exercise, but for the National Leaguers. As expected, the league average is slightly better, as starters have averaged a 7.3 K/9 and 8.6% SwStk%.

Homer Bailey | 9.3% SwStk% | 7.0 K/9

The annual breakout candidate has had a roller coaster season, posting ERAs of at least 6.00 in two separate months, while enjoying sub-4.00 ERAs in every other month. But, he is one non-blowup start away from his first sub-4.00 ERA season. Bailey started the first half of the season quite slowly in the strikeout department. However, he picked it up in the second half, posting a 7.8 strikeout rate, which is much more in line with his SwStk%. Of course, a lower K/9 than his SwStk% suggests happened last year as well, as he posted an identical SwStk% and Contact% and finished with just a 7.2 K/9. Oddly, in 2010, he posted a K/9 above 8.0, yet his SwStk% was well below these past two years.

Pitching at home has been a real problem for him, as in his career his home ERA sits at 5.13 versus an away ERA of 3.95. Not surprisingly, home runs are a big reason why, as he has allowed a 13.2% HR/FB ratio at the GABP, compared with an 8.2% mark away. While his home/away splits might not change as long as he remains a Red, a true breakout might be just half a point in strikeout rate away.

**Well damn did I have good timing with this write up. Obviously, I wrote this before last night’s no-hitter. Bailey’s gem dropped his season ERA to 3.75, so unless he gets absolutely obliterated in his last start next week, he will finish with that sub-4.00 ERA. Oh, and his strikeout rate rose to 7.1, which isn’t much of a change. The conclusion about his strikeout rate still stands, but this may end up looking like his breakout year.

Trevor Cahill | 9.1% SwStk% | 6.9 K/9

Moving from the American League to National League typically helps pitchers, and most notably in strikeout rate. Cahill has been no exception, as his K/9 has risen from 6.4 to 6.9 this season. His SwStk% has surged from 7.6 last year to a career best 9.1%, which certainly justifies the increased strikeout rate. However, I think it should have bounced even higher. At the very least, a 7.3 league average mark should be expected.

His pitch mix changed a bit, as he’s throwing his fastball about 4% more often and his slider and curvball usage has flip-flopped. The latter switch isn’t a big deal since he has induced whiffs are a similar rate with both pitches this year, but he has used his fastball more often at the expense of his change-up. I’m not sure that the spike in SwStk% itself is sustainable and would be more willing to bet that it regresses a bit. But even if it does regress, I think his strikeout rate should remain similar next year.

Ricky Nolasco | 8.5% SwStk% | 5.9 K/9

The man who has broken the heart of stat geeks everywhere. But instead of the other side saying “I told you so”, Nolasco has decided to make it easy on all of us by simply pitching poorly. Whereas it used to appear that he had just been unlucky, his skills have eroded to the point where his SIERA actually matches his ERA for a change, but this time it is not a good thing. While his ground ball rate has actually increased and control remains strong, his strikeout rate has tumbled, declining for a third straight year.

His fastball velocity is down a tick, and now represents its lowest avergae since 2007, but he is also throwing the pitch with the lowest frequency. Not surprisingly, his SwStk% is at its lowest mark since his first two seasons, but it still sits right around the league average, which should have led to a much better strikeout rate than a sub-6.0 mark. While it’s a good bet that his strikeout rate will rebound to at least the mid-6.0 range, the bigger question is if he’ll ever see another sub-4.00 ERA again. Shouldn’t cost much in NL-Only leagues to take the gamble!