Home favourite Jannik Sinner beat Stefanos Tsitsipas in straight sets on the first day of the season-ending ATP Finals in Turin, Italy.
Greece's Tsitsipas, the 2019 champion, struggled to match his opponent and did not force a single break point.
"I was excited to step on court and opening the Finals is really, really special," Sinner, 22, said.
"I knew it was going to be very tough but I think I handled the situation well. I tried to stay aggressive and I am very happy with the performance.
"I am happy to start off with a win and hopefully I can continue with this intensity.