George Evans, a 20-year-old substitute midfielder who is a member of City's Elite Development Squad, found the top corner with an exquisite shot from outside the penalty box in the 85th minute to account for the scoring.
"It took a world-class goal to beat Alex (goalie Alex Bono) and beat us on the day," said Toronto coach Greg Vanney.
Toronto looked to the future in the second half and registered its best scoring chances after sending in teenagers Jordan Hamilton and Manny Aparicio, who made the most of their chance in the limelight.
The game was a meaningless affair, part of the ever-growing cash-generating and brand-improving side of world soccer.
Manchester City, which wrapped up play Sunday in the Premier League, is shoehorning back-to-back MLS exhibition games. Toronto FC looked to the bottom line, adding a third game in a week.
'Maybe it's not the best moment to play a game but it's useful," Manchester City manager Manuel Pellegrini said. "Especially for young players that are with our squad.
"I think maybe Toronto was thinking of its league (play) but it was a good game."
The fans got to see 27 minutes of Sebastian Giovinco and 45 minutes of Argentine striker Sergio Aguero, who led the Premier League in scoring this season. Aguero last played at BMO Field as part of the Argentine squad that won the 2007 FIFA U-20 World Cup.
City attempted 26 shots, only four of which were on target. Toronto had seven shots, three of which were on target.
Spain's David Silva was majestic, pulling the strings for City.
"The best player I've played against, by a long shot," said 21-year-old midfielder Jay Chapman, who had a fine game.
Chapman swapped jerseys with Argentine defender Martin Demichelis after the game.
While the TFC youngsters were starstruck, veterans like goalie Joe Bendik enjoyed the evening but took it in stride.
"It's cool to play a bunch of guys you watch on TV all the time, superstars," said Bendik, who played a third of the game in his comeback from a foot injury.
But he was realistic about what the evening meant. "It was a friendly, it looked like a friendly."
Toronto spent much of the first half chasing the slick-passing tourists as the Canadian women's national team looked on from one corner of BMO Field. The women got a rousing ovation from the announced crowd of 23,169 when they came onto the pitch to take a bow at halftime.
Hamilton wasted little time making an impression, coming close when he sent a shot just wide after a fine run into the box was spotted by Aparicio in the 55th minute. Hamilton came close again 10 minutes later, forcing goalie Willy Caballero to palm the ball away.
The younger version of Toronto FC gave a good account of itself as Man City emptied its bench. Aguero had his chances but could not convert and pleaded unsuccessfully for a penalty when he went down in the 78th minute as a rainbow appeared above the East Stand.
Silva's hard, close-range shot was stopped by Bono's face in the 75th minute, causing the crowd to cringe when the play was shown on the big screen.
A minute late, Aparicio hit the post with a volley off a Jackson feed.
Bright Dike, recalled from loan to San Antonio, had a chance to tie it in stoppage time but headed wide.
Toronto fielded a strong lineup, at least to start with. Regulars Michael Bradley, Giovinco, Benoit Cheyrou, Justin Morrow, Ashtone Morgan and Nick Hagglund started with Bendik returning after a six-game absence due to a foot injury.
The City starting 11 featured three players — Yaya Toure, Aleksandar Kolarov and Silva — who started in Sunday's Premier League finale, a 2-0 win over Southampton. Six other City starters Wednesday were on the bench Sunday.
They played "God Save the Queen" before the game but the only British starter was Toronto striker Luke Moore.
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