“Today was a huge day,’’ said the 34-year-old from San Diego after he’d run away from Kenya’s Robert Cheruiyot in the final 2 miles to win by 41 seconds in 2 hours 9 minutes 15 seconds. “You visualize, you visualize, but when reality hits, it hits home and it’s pretty sweet.’’

Not since Alberto Salazar won his third straight crown in 1982 had a Yank broken the tape in Central Park and not since 1979 had there been so many in the top 10, including Ryan Hall (fourth), Jorge Torres (seventh), Nick Arciniaga (eighth), Abdi Abdirahman (ninth), and Jason Lehmkuhle (10th). “A wonderful day for myself and the rest of the American guys,’’ declared Keflezighi, who collected $200,000 for winning his first laurel wreath in any town - the $130,000 winner’s payout, $40,000 for winning the US title, and $30,000 for going under 2:09:30.

It was a historic day, too, for Ethiopia, which produced its first women’s champion here when Derartu Tulu outkicked Russia’s Ludmila Petrova in the final half-mile to win by eight seconds in 2 hours 28 minutes 52 seconds on a day when three-time champion Paula Radcliffe of Britain was undone by knee tendinitis and ended up fourth behind surprising Christelle Daunay of France.

Tulu, a two-time Olympic gold medalist in the 10,000 meters, had won in London eight years ago but had all but abandoned the marathon after having a second daughter three years ago and was a late addition to the field. “I didn’t really expect to win here, but I did know that I could be a good competitor and I planned to fight until the very end,’’ said the 37-year-old, who was the oldest women’s winner since 42-year-old Priscilla Welch of Britain in 1987.

So did Keflezighi, who’d finished second here in 2004 after winning the Olympic silver medal and third in 2005 and was determined to run assertively yet prudently this time. “My wife told me, you could have won those,’’ he said. “You’ve got to be patient. Don’t lead. That’s why you saw me in the back the whole time.’’

Nobody wanted to lead the way into a headwind, so more than a dozen of the men were content to jog through Brooklyn behind Morocco’s Abderrahime Bouramdane, who kept looking over his shoulder and wondering why he didn’t have company.

Given the withdrawal of five elite contenders, including two-time champion Jelena Prokopcuka of Latvia and 2008 Boston winner Dire Tune, the women’s pack figured to be small. After Boston champion Salina Kosgei of Kenya and Yuri Kano of Japan tripped over each other and went down hard in the fourth mile, it was a four-female race.

So it remained through 22 miles with Radcliffe a step ahead but in desperate trouble. It had been a ruined year for her with foot surgery, hamstring problems, and tonsillitis, and the soreness in her left leg had curtailed her training coming in. At 11 miles the leg acted up but the gentle pace let the world record-holder stay with the leaders. “I was thinking, ‘Hang in, hang in,’ ’’ said Radcliffe, who was bidding to become the first woman to win four titles since nine-time winner Grete Waitz of Norway.

But once the others broke away in the 24th mile, Radcliffe was finished and the race belonged to Tulu, who soon shook off Daunay, then busted the 41-year-old Petrova, who’d also been second last year, in the park. “It turned out it was God’s will that I should win,’’ said Tulu, “and I am extremely happy.’’

Keflezighi, who’d been through the road racer’s equivalent of the trials of Job during the past two years, was both ecstatic and grateful. He’d been favored to win the Beijing trials, but he ended up with a hip stress fracture when he kept running after his calves cramped and he didn’t regain his old form until this year. “I’ve been doing the Prayer of Jabez for a long time,’’ he said, “and every day I’m in the ice bath.’’

Yesterday Keflezighi was nestled comfortably, always in striking distance, and as the other contenders dropped off - Hall, two-time world champ Jaouad Gharib of Morocco, James Kwambai and Jackson Kipkoech of Kenya, two-time champion Marilson Gomes dos Santos of Brazil (a DNF), Hendrick Ramaala of South Africa, and Bouramdane, it was a two-man race between Keflezighi and Cheruiyot, the four-time Boston victor who’d been recruited on short notice after Paul Tergat withdrew.

Had Cheruiyot been fresher - he was fifth in the Berlin world championships in late August - they might have fought all the way to the Tavern on the Green. But when Keflezighi busted his move at 24 miles, he was gone, along with 27 years of star-spangled frustration. The final mile was an emotional victory lap. Central Park was where his Olympic dream vanished, where good friend Ryan Shay had died from heart failure that day, where two chances at victory had slipped away.

This time Keflezighi finished grinning, pointing to the USA on his jersey and giving a thumbs-up to the crowd. When he broke the tape, he dropped to his knees, kissed the ground, and burst into tears. “Man, God is great,’’ proclaimed Keflezighi. “I’m just thrilled to win my first marathon ever at the place where I started and on a PR, wearing that USA jersey. It can’t get any better.’’

John Powers can be reached at jpowers@globe.com.