7-10 split

A split is a situation in ten pin bowling in which the first ball of a frame knocks down the headpin ("number 1 bowling pin") but leaves standing two or more non-adjacent groups of one or more pins. Scoring a spare in this situation is often referred to as a "killer shot".

One of the most infamous of splits is the 7–10 split, often called "goal posts" or "bedposts", where the bowler is left with the leftmost and the rightmost pin in the back row (the number 7 and number 10) to knock down with a single ball to achieve a spare. This is also one of the most difficult splits to pick up.

There are two ways to convert this split. The first is to strike either pin and have it bounce out of the pit area and strike the remaining pin. This not only requires substantial ball speed but the pin must be struck in the right spot. Additionally, a pin flying out from the pit is a fairly rare occurrence. This is made more difficult by variation of the pit design according to the pinsetter system, with the Brunswick A-2 being more prone to bounce-outs than recent machines. Bouncing out on a Brunswick GS-series pinsetter is exceedingly difficult due to a moving curtain at the back of the pit which absorbs the impact, while AMF pinsetters have a higher chance of bouncing out the pin facing away from the ball return of a lane pair. The second method is to strike either pin on the inside with enough velocity to bounce it off the side wall (kickback plate) and rebound onto and across the deck into the other pin. Sliding the pin directly will not work since the ball will fall off the lane before it gets far enough aside the 7 or 10 pin to slide it directly across. Despite this fact, many television shows and movies over the years have depicted the 7–10 split being converted by directly sliding one pin into another. In each case, the "conversion" was rigged by either moving the sliding pin over on a deck without pin spots (giving the ball extra room to slide the pin sideways and making it look like the pin was spotted correctly) or by having some help (human or mechanical) from the pit to "slide" the pin over. Barring such "Hollywood magic" in real life, a freak bounce out of the pit or a side wall rebound are the only realistic ways to convert a 7–10 split.

Mark Roth was the first bowler to pick up the 7-10 split on television on January 5, 1980 at the ARC Alameda Open at Mel's Southshore Bowl in Alameda, California. The only other two professionals to convert this split on television are John Mazza and Jess Stayrook, both of which did it in 1991; nobody has done it on television since. (Roth and Mazza did theirs on ABC broadcasts of the Professional Bowlers Tour, while Stayrook did his on an ESPN telecast. Stayrook is to date still the only one to have done this on ESPN.)

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