The fun-loving wide receiver's trademark smile was gone, replaced by deep concern about Haiti's devastating earthquake and the fate of "countless" relatives who live near the capital city of Port-Au-Prince.
"Aunts, uncles, nieces, nephews. We still have not heard much from them, and my mom is still trying to call them," Garcon said, according to The Associated Press. "I'm keeping in contact with my mom. It's tough to get in touch with people down there because of the phone lines."
The second-year pro was born in the United States, after his parents emigrated from Haiti, and most of his relatives still live in the Caribbean nation. Garcon said there are too many to count.
"The hardest part is just not knowing if they're OK or not," Avril told The Detroit News from his offseason home in Jacksonville, Fla., where he was born. "They really don't have the technology for me to be able to get a hold of anyone. That's really been the hardest part of the whole thing."
Avril has five cousins who live in Haiti, and one of his aunts was visiting him in Jacksonville when the earthquake hit. Avril told The News that his aunt was supposed to return to Haiti on Thursday, but instead will stay in Jacksonville for the foreseeable future.
San Francisco 49ers defensive lineman Ricky Jean-Francois told The Sacramento Bee that he has heard from his older brother in Haiti, but not his grandmother and cousins, who live in Port-Au-Prince.
"In Haiti, everything is made out of cement," said Jean-Francois, whose brother described having to dodge a falling ceiling fan when the quake hit. "There are barely any houses left standing."
Last season, Garcon went back to Haiti for his grandmother's funeral, and he planned to return in April with his charitable organization, the Pierre Garcon Foundation.
But when the 7.0-magnitude quake struck Tuesday, devastating one of the world's poorest nations, Garcon changed the plan. Instead of waiting until spring to help, Garcon jumped onto his Twitter account and started asking fans for help.
At one point, Garcon tweeted: "We need the US military as soon as possible n haiti We need the 4 million Haitian that live out side of haiti to Act now, we need da world!"
As he prepares for Saturday night's AFC divisional playoff game against the Baltimore Ravens, Garcon intends to use the NFL's stage as a pulpit to seek more assistance in the recovery effort.
"That (Twitter) is how we got the pictures out, the word out, that's been really helpful," Garcon said. "Spreading the word and helping others is really what it's all about, and this is the best situation to do that now."
Colts coach Jim Caldwell and teammates offered their support, help and prayers for Garcon, who is coming off a breakout season and is expected to play Saturday despite missing the last two games with a bruised hand.
For Garcon, the hardest part is the uncertainty.
"It's hard, not knowing what's going to happen," he said. "The rebuilding process is going to take forever."
People who want to donate money to help the Haitians can do so via the American Red Cross. By texting "HAITI" to 90999, $10 will be added to your cell-phone bill and go toward relief efforts.
The Associated Press contributed to this report.