Vokoun faced 11 shots in the second period and 16 in the third before forcing Brad Richards to lose control of the puck on a breakaway with 70 seconds to go in overtime. The 26-year-old Czech ended up with 38 saves.
Pederson's second goal in as many games enabled Nashville to get a point for just the third time in seven games. Off a faceoff, three Lightning players nearly broke free on an odd-man rush, but Pederson was able to fire a slap shot from the blue line that beat goaltender Nikolai Khabibulin.
Denis Arkhipov gave the Predators a 1-0 lead 5:59 into the opening period, but Vincent Lecavalier tied it just 38 seconds later.
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