Games played in the last round of a round-robin tournament may inspire match-fixing or tacit collusion if there exists a result allowing both teams to advance. This paper reveals that using head-to-head records as the primary tie-breaking principle might lead to such situations and identifies all possible cases in a single round-robin tournament with four teams. According to our simulations based on the 2016 UEFA European Football Championship, collusion opportunities implied exclusively by the official tie-breaking policy arise with a probability of at least 19%. However, the threat can be partially mitigated by choosing an optimal order of matches.

翻译：在最后一轮圆盘比赛中玩的游戏,如果出现允许两队向前推进的结果,可能会激起对决或暗中串通。 本文揭示,使用头对头记录作为主要的断绝关系原则可能导致这种情况,并找出四个队在单轮盘赛中的所有可能案例。 根据我们基于2016年欧洲足联欧洲足球锦标赛的模拟,完全由官方断开关系政策所隐含的串通机会至少会产生19%的概率。 然而,选择最佳比赛顺序可以部分减轻这种威胁。</s>