This is what friends are for.

A Montreal-area runner who won the men’s race at the GoodLife Fitness Toronto Marathon on Sunday owes part of his victory to a friend who convinced him to show up as he recovers from an injury.

After he crossed the finish line with an unofficial time of 2:37:29, Terry Gehl told reporters he decided Friday night that he would join a friend and go through with the race.

“I decided last, last second to come here, so I’m happy I decided,” Gehl said at the finish line.

Gehl said he almost backed out because he is coming off an injury that prevented him from entering last month’s Boston Marathon, which was marred by a pair of deadly explosions near the finish line.

Mylene Sansoucy of Montreal won the women’s full marathon with an unofficial time of 2:58:08.

Runners honour Boston victims

Before Sunday's race, thousands of runners paused for a moment of silence to honour the victims of the Boston Marathon bombings.

Tributes were visible along the course, as runners wore bibs with an image of a “Remember Boston” ribbon and some wore “Boston: we run with you” T-shirts that are being sold for $26 apiece to raise funds for the Boston Children’s Hospital.

"It’s great to support Boston and the running community and the people who have gone through a horrible tragedy there," Dave Bolan, who was wearing the blue T-shirt, told CP24 reporter Jackie Crandles before the start of the race. "In the home stretch it will be hard to slow down when you know people have gone through such horrible things, and it will be great to show support today."

Organizers say more than 10,000 people are participating in GoodLife Fitness Toronto Marathon events, including about 2,500 runners in the 42-kilometre full marathon, which acts as a qualifier for the Boston Marathon.

There were a lot of last-minute registrations, as people decided to run as a way to show support for victims of the bombings, organizers say.

"Boston was top of mind with all the runners this morning," race director Jay Glassman told CP24 during the event.

The tragedy has also been on the minds of police agencies and race organizers around the world, as they take stock of security measures for marathons.

Glassman said police officers are present along the GoodLife Fitness Toronto Marathon course, as they are every year, and the race has a no-clutter policy, meaning trash is collected quickly and bags are not allowed on the ground in areas filled with participants, volunteers and spectators.

Teen dies near finish, man collapses

The marathon was not without incident, however.

An 18-year-old girl died after collapsing on Lake Shore Boulevard near the end of the run.

Police say the girl was without vital signs after she collapsed and attempts were made to revive her. She was rushed to hospital, where she was pronounced dead.

The teen, who was visiting Toronto, died of health-related issues, police said.

Her identity was not released.

At another point in the race, emergency personnel were called into action when a runner suffered a medical emergency.

As someone performed CPR, paramedics arrived and used a defibrillator to help the man as he lay on the ground.

According to emergency officials, the man was without vital signs when he collapsed shortly before 10:30 a.m.

The man’s vital signs returned and he was transported to a hospital.

In addition to the full marathon, people competed in a half marathon, five-kilometre run and walk, and a team relay event.

The marathon started at Mel Lastman Square under clear and sunny skies at 7:30 a.m. From there, runners made their way along parts of Yonge Street, Bayview Avenue and through downtown Toronto before finishing at Ontario Place.

With files from CP24 reporter Jackie Crandles.

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