The pint-sized Argentina Davis Cup star secured his first ATP triumph in over a year with a brilliant 6-2, 6-3 win over Fernando Verdasco of Spain.
Schwartzman, 25, maintained his excellent record against Verdasco with an excellent performance on the clay courts at the Jockey Club Brasilieiro.
“I’m very happy to break into the top 20,” said Schwartzman. “It’s a very difficult tournament, with top 10 great players in the draw and when the week starts you don’t think you are going to play the finals.”
He now lies 18th in the world – above former Wimbledon champion Andy Murray – and is the first Jewish player to reach the top 20 since Brad Gilbert in 1990.
Schwartzman's achievement earned praise for Argentinian football legend Diego Maradona. Paying tribute on Instrgram, Maradona wrote: "I congratulate the Peque for his triumph in Rio de Janierio. I hope that he keeps earning positions, and I want to tell him that he has my admiration, the same that I feel for all who keep the Argentina flag at the top."