The Russian more than doubled his overall lead of 57sec as he covered a flat course on the Tuscany coast in 50min 46sec. He beat France's Armand de las Cuevas by more than a minute and Indurain by 2:34.
Berzin's success followed his victory on Wednesday in the mountainous fourth stage to Campitello Matese.
Indurain, who based his two Tour of Italy wins and his Tour de France triumphs on time-trialling ability, was never in the hunt yesterday from the first time check.
The Spaniard, though, said: 'I will still win because in the last week there are some big climbs. I wait to see if Berzin can last the distance. It was an extraordinary performance by him and for me a bad day I did not expect.'Reuse content