Third seed Sabalenka struggled on serve, and though the first set was tighter than the scoreline suggests Swiatek fought off moments of pressure to claim the victory in an hour and 24 minutes.
The 20-year-old world number one, who recently lifted titles in in Doha, Indian Wells and Miami, has now won 23 matches in a row and will have a lead of more than 2,000 points in the rankings on Monday.
Swiatek said: "I worked hard this week to adjust properly and to play my best tennis on the surface so I'm really proud of myself. I'm really proud of my team because after yesterday's match it wasn't easy to reset, and also physically and mentally be ready for today."
The Pole's winning streak puts her in esteemed company, with only the Williams sisters, Justine Henin and Victoria Azarenka managing longer runs among female players since 2000.
"It's pretty surreal, honestly," said Swiatek. "A few years ago I wouldn't have even thought about being in this kind of group so for sure right now I need to work harder to keep this streak but I'm just going to take it match by match.
"I'm super proud of myself and really satisfied. These kind of players were my role models when I was growing up so it's great."