After overturning a two-goal deficit to earn a stunning 2-2 draw with Paraguay in their Group B opener, guest nation Qatar almost secured another point until Duvan Zapata broke the deadlock in the 86th minute.
Zapata broke Qatar hearts with four minutes remaining in Sao Paulo, where the Asian Cup holder lost its first competitive match since the Gulf Cup of Nations in December 2017.
"It leaves us with a bad taste because the end was already close," Sanchez said. "Score a goal in final minutes, when the game is tied ... You leave with the bitterness of not being able to score but we also have to value that the team competed with a great rival.
"We played against one of the best teams in the world. Despite the loss, we competed until the final whistle. This will give us strength to keep working and preparing for the future."
James Rodriguez – reportedly set to join Napoli from Real Madrid – provided the assist for Zapata's winner against the 2022 World Cup host.
"We had a very good game. We are on the right track," he said. "When you have [Radamel] Falcao and Duvan you always have a goal."
Zapata's goal made it two wins from two games for Colombia, which advanced to the Copa America quarter-finals.
"It's always like this when you have a team with the obligation to win and another which is very organised and that plays very tight on defence, not giving up spaces," Colombia manager Carlos Queiroz, who led Iran during the 2019 Asian Cup, said.
"If you don't score early, you are going to suffer. We won because Colombia played the way I like Colombia to play, fully focused during the 90 minutes."