The basic premise of a changeup is to change speeds on a hitter making him believe that a fastball is coming, but also to change a hitter’s eye level as well. A great changeup usually is thrown 7-to-10 mph slower than a pitcher’s average fastball and dips down in the zone.

When a pitcher’s changeup is ineffective is when there isn’t much variance in speeds between his fastball and changeup and when it is left up in the zone. That is exactly what happened to Colorado Rockies’ pitcher Jeff Francis yesterday against the San Diego Padres.

 

Francis was rocked for eight runs on seven hits in three innings of work. He also walked three and struck out nobody in his 80 pitch effort. So what was Francis’ downfall on Wednesday? His rather pedestrian changeup.

Out of the 80 pitches Francis threw against the Padres, 47 percent of them were changeups. Only twice did a batter swing and miss at those changeups. It was pretty clear Francis wasn’t fooling anyone on the mound.

There were two main reasons why the Padres pounded Francis’ changeup…

1. Velocity. Going into yesterday’s game, Francis averaged 87.1 mph on his fastball and 79.2 mph on his changeup. That is a solid eight mph difference.

On Wednesday, Francis averaged around 87 mph on his fastball, which is par for the course, but his changeup was coming in at around 82 mph. A five mph difference between a fastball and changeup is not enough to fool major league hitters.

I don’t know if Francis was loosening his grip on his change or he was over compensating for being hit on the arm on a comebacker by Chase Headley in the first, but his change was faster than normal and it hurt him.

2. Up in the zone. Francis could have gotten away with a mediocre changeup if the majority of his pitches were down in the zone. Sadly for Francis, this was not the case against San Diego.

Look at Francis’ strike zone plot courtesy of PitchFX…

His changeups are in yellow. If you click on the chart you will see how many of his 38 changeups were up in the zone. I am counting 26 out of 38 changeups were technically up in the zone.

No pitcher can survive with mediocre stuff up in the zone against good major league hitters.

I am guessing this was just one poor outing by Francis and that his changeup will come back to form in his next start. But man, Wednesday was a rough one for the native of British Columbia.

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