The 20-year-old from Toronto has gone well beyond just hanging around. Osorio earned a starting assignment in the MLS club's first pre-season game against Columbus in Orlando in February, has seen action in 10 of TFC's first 11 league games, scored twice and been singled out for praise by manager Ryan Nelsen, who has used him as an impact substitute.
On Thursday, the soft-spoken Osorio added another chapter to his resume when he was called up for Canada's friendly on Tuesday against Costa Rica in Edmonton.
"It's very overwhelming," Osorio told reporters after Toronto FC's practice Thursday. "Everything's happened so fast, in such a short period of time. I'm really happy. My family's ecstatic. I'm really excited and anxious to get started."
Tony Fonseca, technical director for the Canadian Soccer Association, and interim national team coach Colin Miller no doubt appreciate the enthusiasm. Given that the game does not fall on one of FIFA's international match dates, many clubs were reluctant to release players to Canada.
D.C. United, for example, declined to make Dwayne De Rosario, Dejan Jakovic or Kyle Porter available. The Washington-based team, which currently occupies the MLS basement with a 1-8-2 record, has a U.S. Open Cup game against the Richmond Kickers that same night.
Portland captain Will Johnson wanted to play for his country but his MLS side, which faces the Wilmington Hammerheads the next night in another U.S. Open Cup game, said no.
Adding to the fixture gridlock, the Montreal Impact play the Vancouver Whitecaps in the second leg of the Amway Canadian Championship final on Wednesday.
The Costa Rica game, the first for the Canadian men in Edmonton since 2008, will feature Edmonton natives Tosaint Ricketts and Randy Edwini-Bonsu.
Miller isn't sure what kind of team Costa Rica will send north. The Central Americans, ranked No. 48 in the world compared to No. 80 for Canada, are gearing up for a June 7 World Cup qualifying match against Honduras. But the Edmonton game is being played on artificial turf, which may be a turn-off.
"Will they risk some of their big guns coming into town?" mused Miller, "I don't know, I'm hearing mixed stories."
Miller won't get much time with his own squad. Ricketts, for one, isn't expected in camp until Monday.
"It's not ideal preparations," Miller told a media conference call, adding "I'm certainly not making excuses."
Miller may call up a player or two from his own FC Edmonton team, of the North American Soccer League, if some of those summoned don't make it.
Other Toronto FC players called up are defenders Doneil Henry and Ashtone Morgan and midfielder Kyle Bekker. Only Henry has seen first-team action recently.
The Vancouver Whitecaps provide goalie Simon Thomas while the San Jose Earthquakes furnish defender Nana Attakora.
The other 12 play in Europe, including veteran midfielder Julian de Guzman.
While Miller prefers a 4-4-2 formation, he said he plans to play a 4-2-3-1 scheme after talking to Fonseca, who used it in a March national team game against Japan.
"I want us to be aggressive ... I'm not interested in sitting back, waiting to get beat," Miller said.
Osorio's call-up drew a smile from Toronto's Nelsen.
"I'm really proud of the guy, because his attitude from Day 1 has been absolutely brilliant," said the former New Zealand international. "He's a real big future star for Canada football."
"It's great for the club," he added, "that the guy's come through the academy and now he's a Canadian international literally in two months, three months."
In truth, Osorio never played for the academy. Coming from SC Toronto of the Canadian Soccer League, he signed in the fall and was only invited to Toronto's main camp because several players were away with the Canadian national team in Arizona.
His goal with TFC was just to earn a contact.
"I did not expect any of this to happen this fast, to be honest with you," he said.
While just out of his teens, Osorio has gone a long way to make his soccer dream happen.
He spent two years at Club Nacional in Montevideo, Uruguay, thanks to the connections of coach Jorge Amura at the Clarkson Sheridan Soccer Club in suburban Mississauga and an impressive showing during a South American tour.
He started in the Club Nacional under-19 ranks before making his way into the reserves before deciding to return home at the end of 2011.
"It's funny how things work," Osorio said. "Usually people work hard here and then go away. I went away to come back. It was hard, it was a very hard road for me. But the reward is the sweetest."
Upon his return, things weren't all turning up daisies.
At this time last year, he was out with knee tendinitis and looking for a team. "I was in panic mode," he said.
But he has found a home with Toronto FC.
Miller also served as interim Canadian coach in 2003-2004 and was at the helm in January for games against Denmark (a 4-0 loss) and the U.S. (a 0-0 draw). While he has made no secret of his desire to become permanent manager at some time, he says there have been no discussions with the CSA about running the team during this summer's Gold Cup.
NOTES — Miller was blunt when quizzed why goalkeeper Roberto Stillo, who was in his January camp, had not got another invite. "He didn't show me enough in training to play him," said Miller.
Goalkeeper: Haidar Al-Shaibani, Nimes Olympique (France); Milan Borjan, Sivasspor (Turkey); Simon Thomas, Vancouver Whitecaps.
Defenders: Nana Attakora, San Jose Earthquakes; Andre Hainault, Ross County (Scotland); Doneil Henry, Toronto FC; Ashtone Morgan, Toronto FC; Adam Straith, FC Saarbruecken (Germany).
Midfielders: Kyle Bekker, Toronto FC; Stefan Cebara, Nogometni Klub Celje (Slovenia); Julian de Guzman, SSV Jahn Regensburg (Germany); Issey Nakajima-Farran, Alki Larnaca (Cyprus); Jonathan Osorio, Toronto FC; Pedro Pacheco, CD Santa Clara (Portugal); Samuel Piette, Fortuna Duesseldorf (Germany).
Forwards: Randy Edwini-Bonsu, Eintracht Braunsweig (Germany); Marcus Haber, Stevenage (England); Tosaint Ricketts, Sandnes Ulf (Norway).