Meanwhile, Lagat smashed the world over-40 best, running 27:48 on his competitive debut at the distance, and adding to the plethora of indoor 'masters world bests' he set indoors.
The pace was brisk from the start with a lead group passing through the first kilometre in 2:41, and the second kilometre in 2:43.
A sub-28 minute time didn’t necessarily seem on the cards, given the blustery conditions but a leading group of six were under this schedule as they passed through the 5km mark, at the western-most part of the course, in 13:51.
On the run back towards the centre, the lead group began to break up with Ethiopian youngster Tesfaalem Mehari, world record-holder Leonard Komon, and Wilson Kipsang – who was racing just two weeks after finishing second in the London Marathon in 2:04:47 – dropping off the pace in that order.
Mokoka, who finished third behind Kenenisa Bekele and Kipsang last year, stayed with Sambu but the pre-race favourite broke Mokoka courtesy of back-to-back kilometre splits of 2:38 and 2:41.
Sambu set a negative second-half split of 13:39 to cross the finish-line in a 2015 world-leading time of 27:30.
His winning time was the fastest in Manchester since Micah Kogo set the still-standing course record of 27:24 in 2007, and is the third fastest winning time in race history.
Sambu has run faster in the past but Mokoka made a huge step forward.
Having recently lowered the South African 5000m record to 13:11.44, Mokoka slashed 34 seconds from his 10km best, and took 22 seconds off a national record which had dated all the way back to 1980.
Lagat, who trains alongside Sambu under the tutelage of James Li in Arizona, was thrilled with his performance, his world over-40 best of 27:48 slashed 12 seconds from Gebrselassie’s previous mark, which had been set in this race two years ago.
“You know, I actually even doubted why even I signed up for this!” joked Lagat, who had been picking Sambu’s brains – 14 years Lagat’s junior – ahead of the race.
“This morning he was asking me what the pace was going to be. I told him ‘don’t worry just follow the elite group.’ I told him ‘don’t worry, we have been doing tempo runs together. You have done the training.’ It worked good,” said Sambu, who has been a significant figure on the American road racing scene in recent years.
Gebrselassie, who is slowly winding down his illustrious career, finished back in 16th in 30:05. He said he picked up a small injury after a recent speed work session, and the five-time winner of this race was never up with the leaders today.
Saina’s front-running tactics prevail
In the women’s race, Betsy Saina and Caroline Kilel pushed the pace together from the gun.
The Kenyan duo towed an initial group of five runners on 31-minute pace through the first two kilometres in 3:06 and 3:05 respectively.
After running side-by-side in the opening kilometres, Saina soon took the lead outright, breaking away from Kilel around the halfway point which was covered in 15:41.
In the second-half, Kilel began to pay for her ambitious start, eventually reeled in by Great Britain’s 2014 European cross country champion Gemma Steel and Kenya’s two-time world marathon champion Edna Kiplagat from Kenya in the seventh kilometre.
Saina went through 8km in 25:22, but saw her lead cut slightly to eight seconds
In pursuit of Saina, Steel broke away from Kiplagat but had just a little too much ground to make up.
Saina, who was last year’s fastest 10km runner at 30:46, crossed the finish line at Deansgate in 31:49 with Steel six seconds in arrears.
Having arrived in Manchester fresh from a 15:00.48 season’s opener over 5000m in Stanford, Saina will be diverting her attention back to the track.
Her next race will be over 5000m at the Prefontaine Classic in Eugene, an IAAF Diamond League meeting, but her main goal this summer is to make the Kenyan team over 10,000m at the IAAF World Championships.
Looking further ahead, Saina has marked 2017 as the season she will move up to the marathon.
Kiplagat comprised the podium in third in 31:57 with Kilel fourth in 32:18.
Steven Mills for the IAAF