Egan Bernal secured Paris-Nice glory at the end of a thrilling final stage that was won by Astana's Ion Izagirre.
Team Sky's Bernal assumed the overall lead at the end of the penultimate stage and held on in Sunday's tense finale to take the title at the age of 22.
He was pushed all the way by fellow Colombian Nairo Quintana [Movistar], who had to settle for second place with a gap of 39 seconds to the yellow jersey.
Bernal's team-mate Michal Kwiatkowski – who took the sprinters' jersey – was third as Sky won the race for the sixth time in eight years.
Quintana was frequently the thorn in Sky's side during the 110-kilometre final leg of the route, chasing down Bernal with grim determination to become at one point the virtual race leader.
But despite working well alongside 2018 winner Marc Soler and Hector Carretero, the Movistar trio could not finish the job as Bernal was aided in his triumph by the tireless and selfless Kwiatkowski.
Izagirre crossed the line first as the Spaniard's measured effort saw him prevail on a day when the headlines belonged to Bernal.
1. Egan Bernal (Team Sky) 29:17.02
2. Nairo Quintana (Movistar) +00:00.39
3. Michal Kwiatkowski (Team Sky) +00:01.03
4. Jack Haig (Mitchelton-Scott) + 00:01.21
5. Romain Bardet (AG2R La Mondiale) +00:01.45