Top seed Swiatek, the 2022 and 2023 champion at the German clay-court tournament, saw off former US Open champion Raducanu 7-6 (7/2), 6-3.
Swiatek is the first player to win three straight titles at the same WTA event since Serena Williams completed a Miami Open hat-trick from 2013-15.
Top seed Iga Swiatek crashed out of the Australian Open on Saturday, losing 3-6, 6-3, 6-4 to Czech teenager Linda Noskova in the third round as her bid for a maiden Melbourne Park title and fifth Grand Slam trophy fell apart.
Iga Swiatek came back from the brink to beat unseeded American Danielle Collins in the second round of the Australian Open on Thursday, extending her winning run to 18 matches.
She enters the opening Grand Slam of the year as favourite.
Defending champion Iga Swiatek was sent crashing out of the US Open on Sunday, losing in three sets to Latvia's 20th seed Jelena Ostapenko.
The world number 76 came through 7-5, 6-7 (5/7), 6-2 despite being a break down in both of the first two sets against the reigning US Open and French Open champion
Djokovic took a two sets lead over Hubert Hurkacz in their last 16 clash when play was halted ahead of a locally agreed 11pm night-time curfew
Poland's Iga Swiatek continued her dominance on Parisian clay with a third French Open crown in the last four years, defeating unseeded Czech Karolina Muchova 6-2 5-7 6-4 in a thrilling final to capture her fourth Grand Slam title on Saturday.
The top seed will take on Brazil's Beatriz Haddad Maia in the last four as she continues her bid for a third crown in four years at Roland Garros and her fourth Grand Slam title overall
Two-time champion Iga Swiatek targets a place in the French Open quarter-finals on Monday as the war in Ukraine casts a shadow over the Grand Slam showpiece.
Across 57 matches in 17 Grand Slam appearances in her young career, Swiatek has already won 19 sets to love.But she knows how it feels to be on the wrong end of a bagel, having lost three sets at majors 6-0 herself, although all of those came across her first two Slam appearances in 2019 -- one in a match she won against Monica Puig
Swiatek blitzed 80th-ranked Wang Xinyu of China 6-0, 6-0 on the back of 21 winners as the 22-year-old Pole took another step closer to becoming the first woman since Justine Henin in 2007 to win back-to-back titles at Roland Garros.
The big-hitting Belarusian gained revenge for defeat by her Polish rival in the Stuttgart final a fortnight ago with a thrilling triumph to end Swiatek's nine-match winning streak ahead of her French Open defence
World number one Iga Swiatek on Wednesday called for prize money equality between WTA and ATP events.
World number one Iga Swiatek defeated Australian Open champion Aryna Sabalenka in straight sets to win her second consecutive Stuttgart title on Sunday.
It is Swiatek's first title of a year, and follows her shock fourth-round exit in the Australian Open at the hands of Wimbledon champion Elena Rybakina
World number one Iga Swiatek was knocked out of the Australian Open Sunday as Wimbledon champion Elena Rybakina blew the women's draw wide open by beating the red-hot favourite in straight sets.
World number one Iga Swiatek fired an Australian Open warning to her rivals with a crushing 6-0, 6-1 win over Spanish qualifier Cristina Bucsa on Friday.