#2 French Open 2011 Semifinal
This is the only four set encounter on this list and is at no. 2 purely due to the quality of play between the two players.
Djokovic came into the semifinal not having lost a single match throughout the year till that point. He had won 43 matches in a row. However, Federer seemed unperturbed by that number as he would go on to produce arguably his best performance ever on a clay court.
His forehand and backhand worked wonders as he took the attack to Djokovic, winning the first two sets. The Serb fought back to win the third and was serving for the fourth at 5-4 but was broken by Federer, who then won the match in the tie-break. Unfortunately, he went on to lose the final to Nadal.
Result: Federer d. Djokovic 7-6 (5), 6-3, 3-6, 7-6 (5)
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