Sinner brushes aside Fritz in straight sets to close in on ATP Finals last four
In September, Sinner had to overcome raucous home support to win his last meeting with the American as he claimed victory in the final of the US Open, also in straight sets.
This time, the Turin crowd was noisily behind the Italian.
The hard-hitting Fritz, ranked number five, put pressure on Sinner's serve early in the first set. The American had the first break point of the match in the 14-minute seventh game but could not take his chance.
Sinner responded at once, but wasted three break points in the next game before breaking to 15 in the 10th game to take the set.
The second set also went with serve until the 10th game when Fritz double-faulted on Sinner's first match point.
Victory put Sinner top of the Ilie Nastase group with just Daniil Medvedev to face. The home favourite could still be eliminated with a straight-sets loss.
Fritz faces Alex de Minaur who has lost both his matches so far.
