## 4 Discussion  
Recognizing the performance indicators that contribute to the final score of a match is important in order to direct the training process toward specific goals. Consequently, the purpose of the current study was to identify and measure the contribution of each performance indicator to the final score of a match. We managed: (i) to predict the goal difference between teams in a match and (ii) to identify the contribution of each performance indicator to the match score both for the teams as a whole and for each team individually. The results showed that for the teams as a whole, fourteen variables had the greatest contribution to the outcome of the match. Of these, twelve (shots per quantity of possession percent, missed chances, entrance to the penalty box, chances percent of conversion, key passes accurate, passes, key passes, accurate passes, ratio passes per lost balls, high pressing percent, positional attacks with shots, sum duration of ball possession) had a positive effect, while two (lost balls in own half, ratio dribbles per minute of ball possession) had a negative effect. When we looked at each team separately, the variables that contribute the most to shaping the scores in their matches differ. Shots per quantity of possession percent is the variable with the biggest contribution. In addition, among the fourteen most important performance indicators is the variable positional attacks with shots. Both of the above variables show that the ability of teams to make shots has a significant positive contribution to the final score in their favor. This finding is in agreement with other research that showed that the total number of shots made by a team is an important factor in determining the match outcome [42; 43; 44], but also with the research of [PERSON] et al. (2012) which showed that successful teams make more shots [45]. However, besides the shots, there are also other variables that contribute positively to the final score of the match. Firstly, our research showed that the creation of chances, even if they are lost (chances missed), but also the ability to convert the chances into goals (chances percent of conversion) had a significant positive contribution. Although chances are the factor that determines the variable xG [46], only one study conducted on beach soccer [47] has examined their effect on match score and found that chance creation is a factor that can distinguish winners from defeated teams. Secondly, four variables related to passing and ball possession (passes, passes accurate, ratio passes per lost balls, sum duration with ball possession) are among the fourteen most important. This finding confirms almost all previous research that has examined the contribution of ball possession  
Figure 7: SHAP force plot indicating key team-level performance variables of Lazio FC and their impact on team’s score performance. to match outcome [14; 42; 43; 44; 48; 49; 50]. On the contrary, the research of [PERSON] and [PERSON] (2014) showed that only successful passes help distinguish the games that a team wins [51], while total passes showed the opposite. However, it should be pointed out that this research was carried out with data that concerned only one team. Thirdly, entrance to the penalty box is another variable that we found to significantly contribute to a positive score in a match and this is in agreement with research that had similar objectives [52]. Finally, key passes and high pressing percent (high pressing success rate) have not been examined by relevant research for their contribution to the match outcome. However, other studies showed the importance of key passes to the playing effectiveness of a team [53; 54; 55], but also the usefulness of a successful high pressing because defending near the opponent's goal seems to be associated with success in soccer [56; 57; 58].