UPDATE 12:15 p.m.:
Lelisa Desisa of Ethiopia has won the 119th Boston Marathon in an unofficial time of 2 hours, 9 minutes, 17 seconds.
It's his second victory here. He also won the 2013 race just hours before a pair of bombs exploded at the finish line. Desisa returned after the attacks to donate his medal to the city in memory of the victims.
Caroline Rotich won the women's race in an unofficial 2:24:55. It's the first Boston victory for the 30-year-old Kenyan. She finished fourth here in 2011.
Two years after the bombs killed three and wounded 260 more, the world's most prestigious marathon took a tentative step back toward normal.
UPDATE: 11:15 a.m.:
American Tatyana McFadden has won her third straight women's wheelchair race at the Boston Marathon.
McFadden rolled down Boylston Street to finish in an unofficial 1 hour, 52 minutes, 54 seconds.
McFadden wore a singlet in memory of Martin Richard, the 8-year-old boy who was killed in the 2013 finish line bombing.
McFadden, 25, is a four-time Paralympian and also the reigning champion of the Chicago, New York City and London marathons. She also finished second in the 1 kilometer Nordic skiing sprint in the 2014 Paralympics.
UPDATE 10:45 a.m.:
The fastest man in the Boston Marathon field, Kenya's Patrick Makau, has dropped out.
Makau ended his race shortly after the 5-kilometer checkpoint. It wasn't clear why he dropped out.
The Kenyan's personal best of 2 hours, 3 minutes, 38 seconds made him one of the biggest threats to defending champion Meb Keflezighi's hopes of repeating Monday.
Marcel Hug of Switzerland won the men's wheelchair race.
It took him 1:29:53 for his first Boston win. The 28-year-old finished fourth last year.
Hug deprived Ernst Van Dyk of his 11th Boston Marathon victory. He's already the most decorated Boston competitor with 10 titles.
The Boston Marathon will never be just another race again. The twin bombs at the finish line of the 2013 race made sure of that.
But when the field of 30,000 leaves Hopkinton on Monday morning, the world's oldest annual marathon will take the initial, tentative steps back toward its roots as a world-class sporting event first, and a cause — for fitness, for fundraising, for freedom — second.
"For us, the core principle is the Boston Marathon is an international athletic event focused on competition and excellence," Tom Grilk, the executive director of the Boston Athletic Association, said last week as he prepared for the 119th edition of the race.
"We start there, every time. Including last year," he said. "What happened in 2013 was the closest and perhaps most poignant part of our history, but part of the history. The history going forward would be written by the people who come and run and watch and participate in all the ways that people do."
A year after the explosions killed three people and wounded 260 more, the Boston Marathon got just what it needed: A safe race, an American victory on Patriots' Day, and a chance for runners and residents alike to rally on Boylston Street.
Meb Keflezighi delivered the cathartic victory while becoming the first American man to win the race since 1983.
"We overcame a big thing last year," Keflezighi said. "We can't get those people back. It can never be forgotten; it can never be normal. But we do what we can. I'm delighted to be a part of something positive."
He's back this year, wearing the defending champion's bib No. 1, and hoping that he can repeat his success without the emotional boost he received from the crowds in 2014.
Here are some other things to look for — and one you won't see — in the race:
Keflezighi said the support of the crowd propelled him to victory last year. But without that added boost, he will have a difficult time winning again against a field that includes three Boston champions and the winners of 80 global marathons in all.
Kenya's Patrick Makau is the fastest in the group, having won the 2011 Berlin Marathon in 2 hours, 3 minutes, 38 seconds. Lelisa Desisa, who won the 2013 race and then donated his winner's medal to the stricken city, is one of four Ethiopians who have completed a marathon in under 2:05.
Boston's 2012 winner Wesley Korir is also in the field.
"May the best man and woman win," Keflezighi said. "I'll give it my best shot."
THE WOMEN'S TURN?
Keflezighi ended one American drought by giving the United States its first men's champion since Greg Meyer in 1983. This year, Shalane Flanagan and Desiree Linden are hoping to end a U.S. slump in the women's race that stretches to 1985.
Flanagan, who came in fourth in 2013, led for more than half of the race last year before finishing seventh in an American course record of 2:22:02. Linden came in 10th last year and missed out on the win in 2011 by 2 seconds.
Lisa Rainsberger, known as Lisa Weidenbach when she won 30 years ago, will be the starter for the elite women when they leave Hopkinton at 9:32 a.m.
Runners should expect a wet run from Hopkinton to Copley Square: The forecast for Marathon Monday calls for showers to begin at about the time of the start and continuing for most of the day.
For race organizers, that's just another contingency to prepare for.
"There's always a degree of anxiety because there are so many things you can't control, Mother Nature being the obvious one," said race director Dave McGillivray, who helps plan the event and then runs the course after everyone else is done.
"You're never going to be back on your heels thinking nothing can go wrong. My goal has been to prevent fires, not put them out," he said. "If we're constantly putting out fires, a case can be made that maybe we caused them, and didn't plan well enough."
For those planning to attend the traditional morning Red Sox game before heading over to Kenmore Square to watch the runners go by: The ballclub hasn't been rained out on Patriots' Day since 1984, though there was no game in 1995 because of a players' strike.
Nor are the police relaxing because last year's race went off safely. If anything, authorities will be out in bigger force this year, according to Kurt Schwartz, the Massachusetts undersecretary for homeland security.
Runners should again pack their belongings in a see-through bag. Spectators should expect to be screened before entering key areas, including the start and the finish. Police have also banned drones from the course.
Schwartz said the goal for officials is to provide security without smothering the qualities that make the race a cherished tradition.
"When we're thinking of the Boston Marathon, that's a primary goal," he said. "We could create a 20-yard buffer between the street and the nearest spectator, but it would just so fundamentally change the char of the day, it would be short-sighted."
SITTING THIS ONE OUT
Here is something not to bother looking for: Two-time defending women's champion Rita Jeptoo will not return after testing positive for performance-enhancing drugs. She has been allowed to retain her three Boston titles — for now — but she was stripped of her 2014 Chicago Marathon win and the $500,000 World Marathon Majors bonus she was in line to receive.
Kenya has won six straight women's races and 19 of the last 24 men's races. But sports officials in the county have acknowledged that they have a doping problem that goes beyond Jeptoo. At a ceremony last week, 2014 runner-up Buzunesh Deba of Ethiopia was given the "F1" bib usually worn by the reigning women's champion.
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