There are certain things that do not change in professional baseball. The "Lotte Giants' defense capability" should also be on the list. They are a team that consistently and consistently cannot defend.

Statistics on defense are incomplete compared to batting or pitching. However, there is a way to evaluate defense capability well at the team level, not individual players. The purpose of defense is to convert a hit by a batter into an out. The DER (Defensive Efficiency Ratio) refers to the ratio of balls that have entered a fair area and thus have blocked on-base hits among balls that have had chances to defend. The formula is 1- (hit-homer + on-base plus mistake) / (bat-strikeout-three-ballnet-fit ball). The larger the value, the higher the ratio of out, so the team can be evaluated as a team with good defense.

Since 2015, when the 10-club system was introduced, Lotte ranked 8.3rd on average. It ranked third four times in last place, twice in ninth place, and twice in eighth place. The highest ranking is in 2017 and sixth in 2020. In the past four seasons, Lotte ranked 10th three times and once in ninth place. Even before that, Lotte hardly received any evaluation as "good defense." It was close to the opposite.

What's wrong with him? Of course, defense is played by players. It is generally said that this is due to Lotte's poor defense capabilities. However, defense is done in a space called a baseball field. Is there any problem at Sajik Baseball Stadium, Lotte's home stadium.

Shin Dong-yoon, director of the Korean Baseball Association, addressed the topic in "Professional Baseball Numbus Book 2025," which was published in March to coincide with the opening of the professional baseball season. He argued that Sajik Stadium is a difficult field to defend, and that much of Lotte's defense problems may have been caused by it.

According to the six seasons of the 2019-2024 KBO League, Incheon SSG Landers Field was the highest at 0.688 among the nine baseball stadiums (Jamsil co-uses LG and Doosan). Sajik Stadium was the lowest at 0.655. The gap (0.015) between the eighth and ninth places was larger than the gap (0.014) between the first and sixth places. Based on this standard, Sajik Stadium is the most difficult stadium to defend (see Figure 2).

However, the home team plays nine times more games than the opponent team at the home stadium. If the home team's defense capability is poor, it is natural that the DER of the relevant stadium falls. Therefore, it is necessary to divide the DER of the home team and the DER of the away team.

Figure 3 shows the home team and away team DER of nine stadiums divided during the period. Sajik Stadium was home to the lowest DER. And the away team also had the lowest DER. Regardless of Lotte's defense capability, Sajik Stadium is highly likely to be a difficult field to defend. In general, home team DERs are higher than away teams. As the team plays the most games at home, it is advantageous in terms of "adaptation." However, Sajik Stadium was the only one where the home team DER was lower than the away team DER.

If the home team has a strong and fast batting lineup, the DER in question is likely to deteriorate. Therefore, the DER in question needs to be adjusted once more. We need to compare Lotte's Sajik Stadium with another DER in other stadiums, and the away team's Sajik Stadium with another DER in other stadiums. If both the home and away teams' DERs have decreased compared to other stadiums, the stadium can be evaluated as having high defense difficulties.

Based on this standard, the three stadiums that are difficult to defend are Daegu Samsung Lions Park, Suwon KT Wiz Park, and Sajik Stadium (see Figure 4). And the DER decline was the largest at Sajik Stadium. Daegu saw the away team decline 0.002 and the home team decline 0.003. Suwon saw the away team decline 0.015 and the home team decline 0.002. And in Sajik, the away team was 0.022 and the home Lotte was 0.014.

"Sajik Stadium is in a jagged state"

"The difference in DER cannot be attributed to the difficulty of defense in stadiums. However, DER explains quite a few things," said Shin Dong-yoon, director of the Korean Baseball Association. "It is highly likely that Lotte's defense problem is due to Sajik Stadium's problem."

What does this person think when he played at Sajik Stadium? A Lotte infielder-turned-club coach said of Sajik Stadium, "There is no such thing as an average." He said, "Each stadium has its own characteristics. At some stadiums, ground balls fly stably and quickly. At others, ground balls fly in the air. Players prepare themselves to 'how to defend' in this stadium through experience. However, Sajik Stadium is jagged. Some days the soil on the infield is hard, and some days it is dry."

Sajik Stadium was at the bottom of the DER standings by a wide margin compared to other stadiums. It was the only stadium in the KBO League where the home team was worse at defense than the away team. And in Sajik Stadium, both the home team, Lotte, and the nine away teams lacked defense compared to other stadiums. Several players and leaders who have experienced this stadium have called it a "difficult stadium to defend." If so, Sajik Stadium has a problem with the management of the stadium, and it is highly likely that defensive problems occurred here.

메이저놀이터 "KBO League stadiums are far less controlled than those of Major League Baseball," says Yoon Seok-joon, a former manager of the NC Dinos who specializes in baseball stadiums. For example, in baseball stadiums, conditioners, which are processed soil, are placed under the grass to control moisture. In Korea, conditioners are thin. Measures such as spraying water during games are rarely taken.

The baseball stadium and defense issues are not limited to Lotte. The KBO league has failed to surpass 0.980. A low defense rate indicates that the team has made more errors. It is the only season in which the team failed to surpass 0.980 since 2014 when the team played in the Major League. Mistakes are games in which fans intuitively grasp performance. The management of the stadium needs to be improved in order to show high-quality performance to baseball fans. However, the actual situation is that the team does not have a large budget for managing the stadium.

The Korea Baseball Organization (KBO) had planned to hold a winter meeting in Daejeon on Dec. 4 last year to share its awareness on the issue of managing the ballpark with the clubs. However, the event was canceled the previous day due to the Yoon Suk Yeol's declaration of a martial law.