Article Contents

  • 1. Ball motion shape
  • 2. Unknown pattern evaluation process
    • 2.1. When to stop testing zones
    • 2.2. Changing angles
  • 3. Considerations for the USBC Open Championships
    • 3.1. Team-based process
    • 3.2. Rehearsals
  • 4. Junior Gold considerations
  • 5. Planning for panels
  • 6. Final remarks

With the USBC Open Championships currently running and Junior Gold just a few months away, I encourage bowlers to begin the process of practicing a structured unknown pattern play process. By using an evaluation process designed to identify an unknown pattern, a bowler and/or team can quickly find one to two zones that offer the maximum margin for error, hold, and recovery. This will also provide an opportunity for pattern manipulation and increased scoring.

As a college coach, my teams would practice frequently to throw between 64 and 72 shots during a typical practice session. This helped the team to be warmed up and to also manipulate the fresh pattern on our starting pair. To become proficient, much practice is needed in order to become quick, but not hurried.

Ball motion shape

Before I discuss the unknown pattern evaluation process, I want to start with a short discussion about shape and shape matchup. Over my coaching career, I have employed a six-shape system to help simplify the concept and make it easier to visualize ball reaction matchup. Here are the six shapes with corresponding numbers for communication purposes.


These six ball motion shapes help simplify the concept of matching up and communicating with coaches and teammates.

Below, you’ll see my recommendations for matching up the different shapes to pattern lengths. Consult a USBC Gold coach or an IBPSIA-certified pro shop professional to help you with designing a competition arsenal for short, medium, and long oil patterns to ensure proper shape matchup and shape progression.

This table presents potential reaction shape progressions through the five phases of oil pattern transition.

This table presents potential reaction shape progressions through the five phases of oil pattern transition.

Unknown pattern evaluation process

The philosophy behind my unknown pattern decision-making process is finding both hold and recovery on any pattern, by systematically testing different zones, balls, and release types.

I recommend that a bowler should ...

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Joe Slowinski

About Joe Slowinski

Joe Slowinski, a USBC Gold Coach, is a freelance bowling coach who works with bowlers around the globe. He is currently on assignment with the Philippines. Slowinski is the former Director of Bowling at Lincoln Memorial University, where he served as Program Administrator and Head USBC Collegiate Men’s and NCAA Women’s Coach. The Portland, Maine native has served as the Administrative and Men's Head Coach at Webber International University and served for four years as a Master Teaching Professional at the Kegel Training Center. Slowinski is also the former Director of Coaching and Coach Certification for the National Sports Council of Malaysia. He has coached international teams at the World Championships, Pan American Games, South American Games, and European Championships, helping Belgium win a Gold medal at the 2022 EBF Championship of Champions and coaching Brazil to Gold medals at the 2015 Pam American Games and the 2014 South American Games. He was the 2018 NTCA DII/III Coach of the Year and the 2010 NCBCA Men’s College Coach of the Year.