Davenport won, 7-6 (7-4), 5-7, 7-6 (7-4), to take this title for the third time.
"It's still a long summer to go, but it's a great start," said Davenport. "Anytime you win a tournament, it's exciting, and I hadn't beaten Venus in a number of years."
Davenport beat Venus to claim back-to-back championships in 1998 and 1999. Williams came out victorious in 2000 and 2002, her first title coming against Davenport in the final.
In Sunday's final, Davenport failed to close it out in straight sets. She was broken while serving with a 5-4 lead in the second. Williams rallied to take the second-set tiebreaker, and the two played the final set even, setting up the third-set tiebreak.
Swim Week Miami Beach 2014 [PHOTOS]