Junior Guerra made his official return to the Brewers rotation for the first time since his April 3rd start against the Rockies, when he went down with a calf injury. As I mentioned earlier this year, Guerra is one of only two opening day starters in Brewers history, along with Mark Knudson in 1991 who got sick with a high fever, to miss his second start. And, Guerra is the second Brewer opening day starter to have his second start in May. The other was Ricky Bones in the 1995 strike shortened season.
Luckily for Guerra, his bad luck ends there because during his Friday return against the Diamondbacks, he went six innings, gave up only one solo homer and should have earned a win if not for a blown save by Corey Knebel.
I went to the game on Friday and was able to track Guerra’s performance pitch-by-pitch. Here’s what I found:
| Count | Amount | Count | Amount | Count | Amount |
| 1-0 | 11 | 0-1 | 9 | 0-2 | 4 |
| 2-0 | 5 | 1-1 | 11 | 1-2 | 9 |
| 3-0 | 3 | 2-1 | 5 | 2-2 | 9 |
| 3-1 | 3 | 3-2 | 4 |
Guerra was regularly behind hitters. On 98 total pitches, he threw 43 balls and 53 strikes. He was behind in the count 27 times, even 20 times, ahead 22 times and full 4 times. I’m eliminating first pitch balls in play from the 0-1/ahead category, but for reference there were four.
As a comparison, I tracked a Jeff Samardzja start against the Cubs on Thursday.
| Count | Amount | Count | Amount | Count | Amount |
| 1-0 | 12 | 0-1 | 12 | 0-2 | 5 |
| 2-0 | 2 | 1-1 | 17 | 1-2 | 17 |
| 3-0 | 0 | 2-1 | 8 | 2-2 | 12 |
| 3-1 | 1 | 3-2 | 3 |
Facing 27 batters over seven innings, he was behind 23 times, even 29 times, ahead 34 times and full 3 times.
Samardzija was pitching ahead in the count 29 percent of the time. Guerra was ahead 22 percent of the time. That might not seem like a huge difference, but in 2017, hitters are .198 when behind in the count and .266 when ahead.
Here’s some more season numbers from hitters around the league based on the count:
| Count | Average | Count | Average |
| 1-0 | 0.264 | 0-1 | 0.226 |
| 2-0 | 0.289 | 0-2 | 0.170 |
| 3-0 | 0.304 | 1-2 | 0.172 |
| 2-1 | 0.252 | ||
| 3-1 | 0.265 |
But, being behind and struggling to throw strikes isn’t new for Guerra. Take a look at his 2016 numbers:
| Pitch | Usage % | Strike % | Ball % | Swing% |
| Fourseam Fastball | 52.2 | 25.2 | 34 | 47.6 |
| Sinker | 9.4 | 18.8 | 41.7 | 45.7 |
| Slider | 16.6 | 33.4 | 40.8 | 39.5 |
| Splitter | 21.6 | 26.1 | 44.7 | 48.7 |
Let’s compare that to one of 2017’s top tier pitchers, Dallas Keuchel
| Pitch | Usage % | Strike % | Ball % | Swing % |
| Fouseam Fastball | 9.6 | 19.8 | 33 | 50.5 |
| Sinker | 43.5 | 31.6 | 35.2 | 40.4 |
| Change | 13 | 26.8 | 42.3 | 52.9 |
| Slider | 22.5 | 41 | 35.4 | 43.9 |
| Cutter | 11.3 | 25 | 42.1 | 40.2 |
Now, Samardzija in 2017
| Pitch | Usage % | Strike % | Ball % | Swing % |
| Fouseam Fastball | 16 | 33.5 | 28.7 | 45.7 |
| Sinker | 33.8 | 25.3 | 32.8 | 47.1 |
| Slider | 19.8 | 31.9 | 31.4 | 54.4 |
| Curve | 12.2 | 36.5 | 42.1 | 30.2 |
| Cutter | 5.7 | 20.7 | 40 | 53.5 |
| Splitter | 12.3 | 26.8 | 30 | 63 |
Last year, Guerra didn’t have a pitch he could rely on. Three of his four pitches weren’t in the strike zone 30 percent of the time and his slider was swung at under 40 percent of the time. In contrast, Keuchel can turn to his sinker or slider, and Samardzija a reliable slider and swing inducing splitter. However, despite the raw ball/strike numbers from Guerra’s second start, his control and effectiveness might be improving. And, it’s all on the back of his sinker and splitter.
Guerra introduced his sinker on July 19th last year and from then on threw it 28 percent of the time during his last seven starts of the season. That reduced his fourseam fastball usage by 11 percent, slider by 5 percent and splitter by 3 percent. Further, during his last four starts, he averaged only 8 sliders per game. That was down from the 17 he averaged in his first 13 starts and season high 32 he fired off against the Tigers on June 29th. He kept up his trend of reducing the slider in his most recent start.
| Pitch | Count | Strike | Ball | Whiff | Contact | In Play | Results |
| Fourseam | 39 | 11 | 15 | 5 | 15 | 7 | F9, P4, 4-3, E4, L8, F8, F9 |
| Sinker | 23 | 8 | 9 | 3 | 7 | 3 | F7, 5-3, 6-3, |
| Slider | 10 | 1 | 8 | 0 | 1 | 0 | |
| Splitter | 26 | 7 | 10 | 7 | 9 | 5 | 6-3, HR, 2B, 1B, 1-3, |
Guerra’s slider was borderline ignored, and he didn’t throw it past the fourth inning. Also, he only used it past the second pitch of an at-bat once. It seems it’s main usage was to give hitters something that wasn’t a fastball or sinker on the first pitch. However, it ended up putting him behind in the count 1-0 three times and 2-0 twice.
Looking at Guerra’s overall control numbers from his D’backs start, there’s some major improvement on last season. His sinker, which he could never find the zone with, hit the mark 34 percent of the time. To explain how bad his sinker was in 2016, he threw 31 sinkers during his last two starts and one of them fell in for a called strike and zero induced a whiff. For Guerra to have 8 called sinker strikes, 3 whiffs, and no hard contract is an impressive turnaround.
Guerra’s Splitter has also been devilishly nasty as his main strikeout pitch, and the seven whiffs against it were from Paul Goldschmidt (Badly), Yasmany Tomas (3 times), Chris Ianetta, and Brandon Drury. Last season, Guerra caused 9 whiffs in his final four starts and averaged four whiffs on his splitter per game. Currently, it looks like his splitter is on a different level (ask Goldschmidt) and it could help that he has learned to located the sinker.
However, the splitter could havebeen a victim of overuse when it was clubbed hard, 106 mph both times, for a homer and double in the fourth inning.
But, It’s possible that we may see Guerra morph into a sinker-splitter pitcher. The last six batters he faced looked like this:
| Hitter | Sequence | Result |
| Chris Owings | Split | 1B |
| David Peralta | 4seam, Split, Sinker, | 5-3 FC |
| Paul Goldscmidt | Sinker, Sinker, Sinker, 4seam, Split, Sinker | 6-3 |
| Jake Lamb | Sinker, Sinker, Sinker, Split | 1-3 |
| Yasmany Tomas | Sinker, SInker, Split, Fastball, Split, Split | BB |
| Brandon Drury | Sinker, SInker, SInker, Split, Sinker, Sinker, Split | K |
Adding in Guerra’s fastball, this should be the Guerra we see moving forward and it looks like, and in terms of control and off speed stuff, it could be an improved Guerra. If Guerra can find a way to improve on his 2016 campaign, where he went 9-3 with a 2.81 ERA on a team that only won 73 ball games, it would be an impressive showing from the 32-year-old who debuted just two years ago.