During the Joker-Tsonga Match the commentators showed a slow motion of Novak's footwork compared to his previous game Here were their comments: "Novak was using much lighter white shoes with spikes on the bottom for better grip & better movement" Apparently we all saw how poor Novak moved against Seppi. Never got into proper position and was mostly out of balance before making a shot. Yesterday against Tsonga he went back to his slightly heavier Red shoes and looked like he had better footwork. So could this have been due to shoe change? Also I thought Novak played way better against Tsonga compared to previous round and pushed many games to deuce or atleast 30. Also he was able to find his range of shots fairly early and was well balanced. there was no barrage of unforced errors compared to his match against Seppi match. The question really is: 1.Can shoe change make that much impact? 2.I'm sure Novak would have tested it, but why change shoes in Mid of a tournament? Pls comment!