Halep's shaky serving from her semi-final win the day before carried over at the outset of the final as she produced four double faults and was broken in Sunday's opening game.

The Romanian responded by changing her tactics, drawing the Brazilian into longer rallies to reel off six straight games and sealed the opening set when she blasted a forehand winner, pumping her fist as the supportive crowd roared their approval.

Haddad Maia dominated the second set but got tight in the decider, badly missing a forehand wide to hand Halep a 4-1 lead she would not relinquish.

The two-time grand slam champion sealed her ninth WTA 1000 title when Haddad Maia's service return found the net on match point under sunny skies in the Canadian city.

It was Halep's most significant honour since winning in Rome in 2020.

The 30-year-old former world No.1, who had nine double-faults in the match compared to Haddad Maia's two, left the door open for the South American, who was vying for victory in her first ever WTA 1000 event.

Halep had already clinched a return to the world top 10 by reaching the final in Toronto, the first time since her 373-week stint ended just over a week ago - which led to admissions that she had considered calling it quits amid her decline.

A valiant comeback in 2022 has been one of the major stories of the calendar year though and, on the back of victory in Canada and a semi-final march at Wimbledon, Halep will now have high hopes for the US Open.

Australian Associated Press