RIO DE JANEIRO — Canadian teenager Félix Auger-Aliassime lost 6-3, 7-5 to Serbia’s Laslo Djere in the final of the Rio Open on Sunday.The 18-year-old from Montreal became the youngest player to reach an ATP Tour 500 tournament final since the second of three levels on the circuit was introduced in 2009, but couldn’t notch a fifth consecutive win against an opponent with a better ranking at the clay-court event.Despite the loss, the 104th-ranked Auger-Aliassime is projected to move into the top 60 of the world rankings when they are released Monday. The 90th-ranked Djere, 23, is expected to move inside the top 40.In a match between two first-time tour finalists, Auger-Aliassime and Djere both struggled with their serves.Auger-Aliassime had his serve broken on his first three games with the advantage. He fought back from two breaks down to cut the deficit to 4-3, but Djere then held serve and recorded another break to finish the set.Auger-Aliassime broke back on Djere’s first service game of the second set, but the Canadian’s service problems continued later. Leading 3-2 and with a 40-0 lead in the game, Auger-Aliassime double-faulted twice. He then lost the key game, getting Djere back on even terms.Auger-Aliassime had nine double faults in the match and Djere broke the Canadian six times, including in the final game. Djere finally finished the final game on his fifth match-point opportunity.Auger-Aliassime had 47 unforced errors, 20 more than Djere.Despite the inconsistency from the Canadian, the crowd offered plenty of vocal support for Auger-Aliassime, who wore a Brazilian soccer shirt with his first name on the back after one match earlier this week.Djere was working on more rest as he got a walkover in the semifinals when an injured Aljaz Bedene withdrew. Djere didn’t drop a set all week, while Auger-Aliassime was coming off a three-set semifinal win over Uruguay’s Pablo Cuevas.Auger-Aliassime was the second Canadian in as many weeks to finish as a runner-up at an ATP Tour event. Brayden Schnur of Pickering, Ont., lost in the final of the New York Open, an ATP Tour 250 event (the third level), last week.Milos Raonic was the last Canadian to win an ATP singles crown, capturing a 250 event in Brisbane, Australia, in January 2016.While clay traditionally is not the strongest surface for North Americans, Auger-Aliassime skipped the grass-court season last year to play lower-level events on clay to gain experience. Auger-Aliassime recorded the decisive win in a Davis Cup tie against host Slovakia on clay earlier this month before enjoying his breakthrough run in Brazil.Auger-Aliassime is scheduled to stay in the country for the Brasil Open, an ATP 250 event this week in Sao Paulo. He’ll have a rematch with Cuevas in the first round.