사이드 암, side arm

 

 

던지는 팔의 반대방향으로 허리를 수평하게 비틀면서 중심 이동에 따라 몸을 반전할 때 팔을 지면에 수평하게 뻗어 볼을 던지는 투구폼을 말한다. 별칭으로 옆구리 투수라고도 불린다. 각주에도 나와있듯, 릴리스 포인트가 던지는 팔의 어깨 높이와 거의 같거나 약간 낮은 곳에서 형성된다.

위로 던지는 두 가지 폼(오버핸드 스로, 스리쿼터 스로)에 비해 볼끝의 횡적 변화를 강조할 수 있는 투구폼. 내리꽂는 폼이 아니기 때문에 중력의 도움을 받을 수 없으며, 이로 인해 발생하는 디메리트를 상쇄하기 위해 팔꿈치와 손목의 힘이 강조되는 점이 포인트. 오버핸드 스로나 스리쿼터 스로는 릴리즈포인트가 흔들리면 종 방향 제구에 난조가 오는 반면 사이드암 스로는 횡 방향 제구가 흐트러진다는 것이 특징이다. 반대로 말하면 일정 수준에 오를 경우 바운드볼 블로킹에 취약한 포수와 궁합이 좋다.

한편 위에서 언급한 횡 방향 제구가 흐트러진다는 특징 때문에 오버핸드/스리쿼터 스로에 비해 몸에 맞는 공을 허용하는 비율이 높다. 통산으로 보나 개별 시즌으로 보나 몸에 맞는 공 허용 순위를 보면 로테이션을 꾸준히 지킨 사이드암/언더핸드 스로 선발투수들이 상위권을 차지하고 있다. 통산 몸에 맞는 공 1, 2, 3위인 이강철, 임창용, 박종훈은 모두 옆구리 투수이고, 2020년 KBO리그를 예로 들면 몸에 맞는 공 허용 1위인 박종훈(22개 허용)은 언더핸드 스로, 2위인 한현희(14개 허용)는 사이드암 스로이다. 심지어 사이드암 선수인 정우영은 시즌 내내 불펜으로만 등판한 덕에 규정이닝의 절반 정도인 75이닝만 소화하고도 11개 허용으로 공동 5위를 차지했을 정도. 똑같이 공동 5위에 오른 오버핸드/스리쿼터 스로 선수인 루친스키, 켈리, 핀토가 각각 183이닝, 173.1이닝, 162이닝을 소화한 점을 보면 사이드암 선수가 얼마나 많이 몸에 맞는 공을 허용하는지 알 수 있다.

팔꿈치를 축으로 하여 나머지 팔을 강한 스냅으로 휘두르기 때문에 곧잘 채찍에 비유되곤 하며, 메이저리그 명예의 전당 최초의 5인에 빛나는 레전드 월터 존슨이 굉장히 긴 팔로 채찍을 휘두르듯 공을 뿌렸었다는 이야기가 특히 유명하다.

더욱이 투구법의 특성상 자신과 같은 손 타자에게는 강하지만 반대 손 타자에게는 태생적으로 약하게 된다. 좌완 투수가 우타자 상대, 우완 투수가 좌타자 상대를 할 경우엔 공이 먼 바깥에서부터 평행한 궤적을 그리며 다가오는 느낌을 주기 때문에 상대적으로 공략 당하기 쉽다. 물론 정통파라도 이러한 반대손 스플릿은 나타나지만 팔 각도가 수평한 사이드암 스로는 그런 경향이 특히나 더 강하다. 이를 싱커나 써클 체인지업 등의 구종으로 약점을 보완하려 하지만 아무래도 상대 방향 타자 상대는 쉽지 않은게 현실. 이 때문에 우타자가 태생적으로 많은 야구라는 스포츠 특성상, 우타에게 약한 좌완 사이드암 스로는 매우 드물다.

그래서 긴 이닝, 많은 타자를 상대해야하는 선발 투수로 롱런하기는 쉽지 않고, 현대 야구로 오면서 사이드암 투수는 불펜으로 많이들 가고 있다. 물론 선수에 따라 사이드암에서 유독 강력한 구위로 윽박지르는 특이 케이스가 있기도 하다. 그리고 좌완 선발을 구하기 어려운 경우 선발투수 로테이션 레파토리를 조금이나마 다양하게 할 수 있는 방편 중 하나가 우완 사이드암인지라 4이닝 이상 소화할 수 있는 능력이 검증된다면 하위선발 후보를 노려볼 수는 있다.

위 단점들에도 불구하고 일정 경지에 올라 온 사이드암 투수는 강력한 메리트를 하나 가지고 있는데, 공을 잘 채는 사이드암 투수의 패스트볼은 굳이 투심/싱커가 아니더라도 포심조차 자연스럽게 상당한 수준의 테일링 무브먼트를 띄게 된다는 점이다. 이는, 우완 사이드암 투수가 포심을 던질시 공의 회전방향은 투구판 기준 좌측(3->1루 방향)으로 형성되는데, 매그너스 효과로 인해 양력이 우측으로 작용하며, 오버 핸드 투수와 달리 중력의 영향으로 상쇄되는 것도 적기 때문에, 강력한 테일링 무브먼트를 형성하게 된다. 오버핸드 패스트볼이 종 변화로 인해 히팅포인트가 점으로 형성되는 데에 비해 히팅 포인트가 횡선으로 형성되어 헛스윙을 이끌어내기는 어려우나 스윗 스팟을 빗겨나가 배트 안쪽에 맞는 타구를 양산해 맞춰잡는 투수로 특화되어 본인의 노력에 따라 상대적으로 투구수를 아낄 수 있다. 거기에 기본적으로 사이드암 투수는 오버핸드에 비해 적은 편이기에 희소성이라는 장점도 있는 만큼 종으로 떨어지는 변화구는 삼진 잡기가 어렵다는 사이드암으로서의 단점을 벌충하는건 물론 일반적인 투수와 수준급 투수를 가르는 결정적 차이가 된다.

 

It refers to a pitching form in which the arm is stretched horizontally to throw the ball when the body is inverted according to the movement of the center while twisting the waist horizontally in the opposite direction of the throwing arm. It is also called a side pitcher by nickname. As shown in the footnote, the release point is formed at approximately the same or slightly lower shoulder height of the throwing arm.

Compared to the two forms thrown upward (overhand throw, three-quarter throw), the pitching form that can emphasize the lateral change of the tip of the ball. Because it is not a downward-slugging form, it cannot be helped by gravity, and the strength of the elbow and wrist is emphasized to offset the demerit caused by this. Overhand throw or three-quarter throw is characterized by disturbance in the longitudinal control when the release point is shaken, while side arm throw is characterized by disturbance in the lateral control. On the other hand, if it reaches a certain level, it is good to be compatible with the catcher who is vulnerable to blocking bound balls.

Meanwhile, the ratio of allowing balls that fit the body is higher than that of overhand/thri quarter throws due to the disorganized lateral control mentioned above. In terms of overall performance and individual seasons, the number of balls allowed that fit the body is high among the starting pitchers for side arms/underhand throws who have consistently maintained their rotation. Lee Kang-cheol, Lim Chang-yong, and Park Jong-hoon, who are the first, second, and third-ranked balls that fit the body, are all side pitchers, and Park Jong-hoon, who is the first-ranked player to allow balls that fit the body, is an underhand throw, and Han Hyun-hee, the second-ranked player, is a side arm throw, for example in the 2020 KBO League. Jung Woo-young, a side arm player, even played only 75 innings, about half of the prescribed innings, and tied for fifth place with 11 allowances. The fact that Luchinski, Kelly, and Pinto, who tied for fifth, played 183 innings, 173.1 innings, and 162 innings, respectively, shows how many hit-by-body balls the side arm players allow.

It is often compared to a whip because the rest of the arm is swung with a strong snap around the elbow, and it is especially famous to say that legendary Walter Johnson, the first five-man Major League Hall of Fame player, threw the ball as if he was wielding a whip with a very long arm.

Moreover, due to the nature of pitching methods, it is strong against hand batters like himself, but weak against the other hand batters by nature. When a left-handed pitcher faces a right-handed batter and a right-handed pitcher faces a left-handed batter, the ball is relatively easy to be attacked because it feels as if it is coming in parallel from the far outside. Of course, even the orthodox school sees such opposite-handed splits, but the tendency is particularly strong for side-arm throws with horizontal arm angles. Although the opponent team tries to compensate for its weaknesses by playing games such as sinker and circle changeup, the reality is that it is not easy for the opponent team to face. Due to the nature of baseball, which has many right-handed hitters in nature, left-handed side-arm throws, which are weak against right-handed hitters, are very rare.

Therefore, it is not easy to run for a long time as a starting pitcher who has to face many batters in long innings, and with modern baseball, many side-arm pitchers are going to the bullpen. Of course, there are unusual cases where some players threaten with a particularly strong pitch in the side-arm. And if it is difficult to find a left-hander starter, one of the ways to diversify the rotation repertoire is the right-hander's side-arm, so if the ability to play more than four innings is verified, the lower-order starting candidate can be targeted.

Despite the above shortcomings, the side-arm pitcher who has reached a certain level has a strong merit, and the fastball of a side-arm pitcher who is good at kicking the ball naturally has a considerable level of tailing movement even if it is not a two-seam/sinker. This means that when a right-hander throws a four-seam pitcher, the direction of rotation of the ball is formed on the left side (3->1 base direction) based on the pitching board, and the lift acts on the right side due to the Magnus effect, and unlike overhand pitchers, it is rarely offset by the influence of gravity, so it forms a strong tailing movement. While overhand fastballs are formed as a point for the heating point due to the vertical change, it is difficult to draw a swing because the heating point is formed in a horizontal line, but it is specialized as a pitcher who misses the sweet spot and mass-produces a hit that hits the inside of the bat, and the number of pitches can be relatively saved depending on his efforts. Basically, side-arm pitchers are less than overhand, so there is also an advantage of scarcity, so it is a decisive difference between the general pitcher and the high-quality pitcher, as well as making up for the shortcomings of the side-arm that it is difficult to strike out.