Inside Pitch Magazine, July/August 2022

Quick Pitch: Structured Bullpens

By: Adam Revelette

Just Verlander in Tigers jersey in bullpen throwing a pitch to catcher that is in backgroundThere are many ways to develop pitchers physically, but perhaps none more important than developing and executing a sound plan in the bullpen. An effective bullpen progression can help lay your program’s foundation for your pitching staff.

Fastball control: There are several times during a season at every level of baseball where everyone just wants the pitcher to throw strikes. How many bullpens have been dedicated to strikes and nothing else? If you can’t throw the ball down the middle, it’s hard to do anything else. Most successful basketball teams begin their pregame routines in layup lines. A set of four-seam fastballs (no, not two-seam) down the middle will enable you to determine who is ready to “advance.”

Fastball command: Only when you have mastered the ability to control the fastball can you truly learn to command it. That is why practicing throwing it straight (hence the four-seam) down the middle is so importance. Once you know how to throw the ball straight, it’s much easier to move it around. The ability to simply move the fastball from one side of the plate to the other can help you get a lot of outs.

Creating a terminology for fastballs is simple yet important: Glove side (1B side of the plate for RHPs), arm side (3B side of the plate for RHPs), and up (above the letters, below the chin, on the plate). Glove side (GS) fastballs will enable your pitchers to feel extension in their delivery and see the fastball finish through its target. You are likely to see more tail/sink when you move to arm side (AS) fastballs, which is a prime location for two-seamers. You can also move the ball off the plate (OFF) both directions to represent 0-2 counts, or pitching around a batter. On that end, the fastball UP can also be repped, which is a difficult pitch to command, but if done correctly can result in swings and misses for pitchers who have high spin/carry or have not developed a true out pitch. An example of a 20 pitch fastball command pen: 

From the stretch: 2 GS OFF, 4 GS, 2 AS OFF, 4 AS, 2 UP

From the windup: 4 GS, 2 AS

Breaking ball/Changeup development: Building in off-speed pitches during a bullpen session can be tricky. A lot of pitchers just rip off consecutive breaking balls or changeups until they get a good feel for them. This can work in some settings, but can result in bad habits over time, such as changing an arm slot or slowing down arm speed. Mixing fastballs with off speed pitches is an ideal way to help your pitchers repeat their deliveries and prevent opposing hitters from picking up cues:

Breaking ball (BB) development: (30 pitches) stretch - 4 GS, 4 BB, 4 AS, 2 UP, 2 BB; windup - 3 GS, 2 BB, 3 AS, 3 BB, 3 GS

Changeup (CH) development: (30 pitches) stretch - 4 GS, 4 AS, 4 CH, 2 UP, 2 CH; windup - 3 GS, 3 AS, 4 CH,43 GS

You may have to make adjustments for pitchers who have off speed offerings beyond one breaking ball and one changeup. Since the GS fastball promotes extension and finishing pitches, it is wise to throw breaking pitches to that side of the plate. This is also true for throwing changeups off AS fastballs, which typically tail/sink more towards the arm side.

Sequencing: Once your pitchers reach a certain point in their development, you can begin executing sequences that come up often in game play. Depending on what your pitcher does well and what kind of offense you’re facing, sequences can vary, but they basically refer to 4-5 pitch sets that mix multiple pitches to both sides of the plate, and include a chase pitch (FB UP or off-speed off the plate/down).

Scripts: Having pitchers execute their pregame scripts is the last step of the bullpen progression. These pens are typically held within a playing season as a means to stay sharp with what your pitcher does well, i.e. their routine. You are emphasizing execution more than development in these cases, which is important when you are talking about winning and losing. This is the same script that your relievers will lean on throughout the season as they prepare for in-game outings. Having a semi-fixed routine can help them prepare more consistently with their ultimate objective being to perform consistently!


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