The aim of this study was to describe and identify the weight of some key career indicators (KCI) on the competitive level of retirement (professional vs. non-professional) of Portuguese football players. Three thousand five hundred retired Portuguese football players born between 1950 and 1989, and registered on Portuguese Football Federation were considered in this study. Descriptive analysis and a multivariable binary logistic regression model were performed to assess the relationship between the mastery stage development variables and the competitive level of retirement of football players. The results highlighted that the KCI first senior registration level, number of seasons in mastery stage, number of total games as senior player, number of total games in retirement season, and the age of the last best result achieved contribute to explain and predict the competitive level of retirement of Portuguese football players. The tendencies identified and their impact on the competitive level of retirement could be important implications on awareness and definition of management and support programs of players’ careers.

中文翻译：

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确定葡萄牙足球运动员的关键职业指标

本研究的目的是描述和确定一些关键职业指标 (KCI) 对葡萄牙足球运动员退休竞争水平（职业与非职业）的权重。3500 名出生于 1950 年至 1989 年之间并在葡萄牙足协注册的退役葡萄牙足球运动员被纳入本研究。进行描述性分析和多变量二元逻辑回归模型以评估掌握阶段发展变量与足球运动员退役竞争水平之间的关系。结果突出显示，KCI第一高级注册级别，掌握阶段的赛季数，高级球员的总比赛次数，退役赛季的总比赛次数，而上一次取得最好成绩的年龄有助于解释和预测葡萄牙足球运动员退役的竞技水平。确定的趋势及其对退休竞争水平的影响可能对球员职业生涯的管理和支持计划的认识和定义产生重要影响。