Uganda's Jacob Kiplimo and Ethiopia's Senberi Teferi were victorious in the opening race of the 2018-2019 International Association of Athletics Federations Cross Country Permit series at Burgos in Spain.
In windy conditions the 15th Cross Internacional de Atapuerca produced a third successive win for the Ethiopian, while world under-20 cross country champion Kiplimo, who turns 18 on Wednesday (November 14), went one better than the second place he managed in this race last year.
Last year's men's winner Getaneh Molla was unable to defend his title due to visa problems, but Kiplimo overcame a field stacked with talent and experience.
Kiplimo, who also took world under-20 silver in the 10,000 metres two years ago, was the first to lift the pace in the men's nine kilometres race when he took command after 10 minutes.
Among those tracking him were Eritrea's world half marathon bronze medallist Aron Kifle, Bahrain's 2016 winner of this race, Aweke Ayelew, Kenya's world under-20 5,000m champion Edward Zakayo, and 21-year-old Ethiopian Abadi Hadis, the current world cross country bronze medallist.
Also in the hunt was the Ethiopian who beat Mo Farah to the world 5,000m title in London last summer, Muktar Edris.
Kifle briefly took over after the second circuit, but Kiplimo soon accelerated to the front again and the Eritrean was the only runner to go with him.
By the bell, Kiplimo and Kifle had a 20m advantage over the triumvirate formed by Ayalew, Zakayo and Hadis.
With 1,500m to go Kiplimo made his final move, building a 13-seconds advantage by the time he crossed the line in 25min 10sec.
Kifle was second in 25:23, with Zakayo two seconds behind him and Hadis just one second further back.
Britain's Andy Vernon was the first European home in 12th place.
"Today's was a very important win for me, my first IAAF permit victory after several second places," said Kiplimo.
"I came here very well prepared and I'm very satisfied because I could hold off the challenge of all my rivals."
The women's 8km event, which preceded the men's race, kicked off conservatively, with the two favourites, Teferi and Kenya's Gold Coast 2018 Commonwealth 5,000m silver medallist Margaret Chelimo, who took second place behind her in the previous year's race with both being given the same time - staying in the pack.
As the pace increased, thanks to Kenyans Norah Tanui and 19-year-old Gloria Kite, Sweden's Meraf Bahta, silver medallist at last year's European Cross Country Championships, dropped off the lead group.
Only the two favourites could stay with the leaders, and midway through the closing lap it was Kite's turn to drift back.
Teferi, world cross country silver medallist in 2015, made her final break inside the last kilometre, and although Chelimo tried to match her the task proved too great.
The Ethiopian won in 25: 51, with Chelimo two seconds behind her and Tanui two seconds further back.