目的：本研究探討2012奧運桌球男子單打比賽與莊智淵五場單打比賽的關鍵球比分決勝的機率，藉以說明關鍵球處理的重要性，並且歸納2002－2012中國乒乓球隊封閉訓練中關鍵球處理的訓練方法，提供教練和選手訓練和比賽的參考。方法：本研究採用文獻探討結合桌球技術分析等方法進行分析。關鍵球的定義為比賽時雙方選手在比分皆進入8分以後至一方取勝之比分。結果：2012奧運男子單打比賽統計，局數為4：0，關鍵球比分的機率為19%；局數為4：1、4：2、4：3，關鍵球比分的機率分別為39%、38%、37%，而莊智淵的五場比賽，其中32強、16強、8強均獲勝，關鍵球比分的機率為25%、0%、0%；四強賽1：4負，關鍵球比分的機率為60%，關鍵球獲勝機率為33%；銅牌賽2：4負，關鍵球比分的機率為67%，關鍵球獲勝機率為25%。顯示莊智淵未能奪牌的主因在關鍵球處理這個環節。結論：提高關鍵球處理的能力，是增加選手奪牌機率的重要因素，其訓練方法有：一、比分情境模擬，藉由六種訓練手段來增加關鍵球的得分能力；二、建立主要對手的比賽資料庫；並針對其關鍵時刻的心理特性與擊球習性擬定比賽策略；三、掌握對手打法與弱點，積極主動進攻並控制比賽節奏。

Purpose: In this study, we analyzed the matches played in the 2012 London Olympic Games of the men's singles and Chuang Chih-Yuan's five matches to derive the percentage of games that entered the game-point situation. This is to reveal the frequency and importance of the game-point situation and the need for athletes to prepare for the situation. Team China's ＂closed training＂ program for the game-point situation is discussed in this study to help coaches plan for the future training program. Methods: This study focused on the 2012 London Olympic Games and used bothliterature review and table tennis technical analysis to examine the games that entered the game-point situation. Game-point situation is defined as the scores that reach 8:8 and after (until one side wins the game). Results: In men's singles, the percentages of the games reaching the game-point situation were 19%, 39%, 38%, and 37% when the game margins of the two players were 4:0, 4:1, 4:2, and 4:3, respectively. In Chuang's first three matches, the percentages of the games reaching the game-point situation were 25%, 0%, and 0%, when he played at the levels of top 32, top 16, and top 8, respectively. He won the three matches. In comparison, at the top 4 and bronze medal competitions, the percentages of the game-point situation were markedly higher at 60% and 67%, in which he lost at 1:4 and 2:4 in respective matches and only had a 33% (top 4) and 25% (bronze medal) game-point winning percentage. The result indicated that Chuang cannot control the game-point situation when he faced the elite world-level competitors in this event. Conclusion: Our analysis reveals the importance of having a game-point training program to prepare for the world-level competitions. The program should include: (1) simulation of the game-point situation to help athletes be alert and ready for the game-point competition, (2) establishing video databases to help analyze opponents' tendency and mentality in the game-point situation, and (3) formulating scouting reports with opponents' stroke patterns and weakness; this is to help athletes stay active on offense while facing of the game-point situation.