Dimitar Berbatov scored the first goal and set up a second to help Manchester United beat Celtic 3-1 Friday in a friendly match.
Georgios Samaras found the net for Scotland's Celtic at baseball and NFL venue the Rogers Centre, which installed a temporary grass field for the match.
Welbeck put it away in the 79th when Berbatov set him up to poke the ball past Lukasz Zaluska.
"The second goal killed the game," Manchester United manager Alex Ferguson said. "A really fantastic goal, too. Marvelous bit of football from Berbatov."
Cleverley's shot in the 86th changed direction after hitting a Celtic defender.
United was without its World Cup players - England's Wayne Rooney and Michael Carrick, France's Patrice Evra, Serbia's Nemanja Vidic and South Korea's Ji-sung Park - and some injured ones, including captain Gary Neville, Rio Ferdinand, and Owen Hargreaves.
But Berbatov was there to lead Manchester United to the win in front of a crowd of 39,193.
"Second half there were some fantastic moments he produced," Ferguson said. "It underlines the one great factor, that class he has. You can't take that away from him."
Mexico forward Javier Hernandez is due to join the team in Houston on July 27, as the team's five-stop North American tour continues. Man United visits Philadelphia, Kansas City, Missouri and Guadalajara, Mexico.
Celtic, which opened its North American tour Wednesday with a 1-0 loss to the Philadelphia Union, plays the Seattle Sounders on Saturday.
"I was really pleased with them tonight," Celtic manager Neil Lennon said. "I thought the level of performance was excellent. A lot of positives to come out of the game. For 75-80 minutes, our performance was very, very good - against one of the top teams in Europe."