After what was probably Tim Lincecum‘s worst major league start, Dave Cameron wondered if something’s wrong with San Francisco’s mop-topped ace with the acrobatic delivery. Cameron noted Lincecum’s month-by-month splits:

April: 1.78 BB/9, 10.85 K/9, 49.4% GB%, 2.25 xFIP
May: 5.70 BB/9, 9.91 K/9, 50.5% GB%, 4.10 xFIP
June: 3.38 BB/9, 9.56 K/9, 41.6% GB%, 3.23 xFIP
July: 3.38 BB/9, 7.09 K/9, 44.3% GB%, 4.06 xFIP

From 2007 to 2009, Lincecum had two months (June 2007, September 2007) where his xFIP was over 4.00. He’s now done it two of the last three months. He’s never had a month with a strikeout rate as low it is right now in July.

With Lincecum merely pitching very well as opposed to dominating, I thought it would be worth taking a closer look at the 26-year-old’s month-by-month performance. Here are his plate discipline stats:

Lincecum’s in-zone contact rate has climbed each month, and it’s actually above the major league average in July. Opponents are also putting the bat on the ball more on pitches out of the zone this month, which helps explain the lower K rate. His swinging strike rate has declined each month, sitting slightly above the MLB average in July.

He’s throwing more first pitch strikes, but they’re getting hit harder than is the case for most other pitchers. First pitches that batters decide to swing at are typically creamed, but even compared to the big league average, hitters are faring well vs. Lincecum on the first pitch. Baseball-Reference has a stat called sOPS+, which compares a pitcher’s performance in a given split to the league average. One-hundred is average, and more than 100 means a pitcher is doing worse than most. Lincecum’s sOPS+ on the first pitch is 159 this season. I doubt there’s much predictive value here, but it’s worth noting.

How about Lincecum’s Runs/100 values?

It’s important when looking at these numbers to consider that pitches aren’t thrown independent of one another. The effectiveness of one pitch affects the others, and game theory comes into play as well. It’s not as simple as looking at the chart, seeing a certain pitch is doing well on a per-pitch basis and concluding that the pitcher should toss pitch X more in place of pitch Y. Hitters become privy to changes and adjust, too. If a pitcher makes a change in pitch selection, the batter may notice and start looking for that pitch more often.

With that being said, Lincecum’s fastball has remained effective on a per-pitch basis, while his secondary stuff has posted below-average run values. In terms of pitch selection, Lincecum’s going to his fastball more and his changeup less. His percentage of fastballs thrown has gone from 52.9% in April to 58.7% this month, with his changeup percentage going from 26.3% in April to 20% in July.

While hitters aren’t doing a whole lot with Timmy’s fastball, they’re not whiffing at it as much — 3.1% in July, according to TexasLeaguers.com. That whiff rate was 5.4% in April, 8.8% in May and 6.6% in June (5-6% MLB average). His changeup was whiffed at 34% in April, 24.5% in May, 30.9% in June and 24.3% this month (12.6% MLB average). The whiff rates on his breaking stuff have typically been below-average throughout the year — 8.2% for the curve (11.6% MLB average) and 10.5% for the slider (13.6%).

Given the poor run values on Lincecum’s secondary pitches and the spike in contact (particularly on pitches thrown outside of the strike zone), it’s clear that hitters haven’t been fooled as much recently when Lincecum winds up and fires. That being said, it’s imperative to not make a rash decision based on what may very well be a temporary dip in performance. Even the best players in the game go through stretches during which they’re not at the top of their game. Lincecum has been one of the best pitchers on the planet since 2007, and making a knee-jerk transaction at this point has the potential to backfire horribly. Keep a close eye on The Freak, but don’t freak out.