Monte Carlo champion Tsitsipas brushed aside Felix Auger-Aliassime, the Canadian who recently teamed up with Toni Nadal, the uncle and former coach of the 20-time Grand Slam winner.
Greek second seed Tsitsipas, fresh off his first Masters 1000 crown, extended his winning run to eight matches with a 6-3, 6-3 victory.
"It feels good to be able to play the way I am. I really hope the winning streak continues," he said.
The Greek will next face rising Italian star Jannik Sinner after the 19-year-old made another significant breakthrough, defeating the Russian Andrey Rublev 6-4 6-7 (4-7) 6-4.
Rafael Nadal has brushed aside Britain's Cameron Norrie 6-1 6-4 to break into the semi-finals of the Barcelona Open and move closer to a record-extending 12th title at the event. Nadal is to face Carreño.
