BOSTON — The rest of the world can debate whether Geoffrey Mutai set a record when he blistered the Boston Marathon course in 2 hours, 3 minutes, 2 seconds — the fastest anyone has ever run 26.2 miles.

From Hopkinton to Copley Square, there is no doubt.

“We had a stunning performance and an immensely fast time here today,” Tom Grilk, the head of the Boston Athletic Association, said on Monday. “We in Boston are well-pleased with what has happened, and that’s good unto itself. The definitions of others, I will leave to them.”

Mutai outsprinted Moses Mosop down Boylston Street to win by 4 seconds, and the two Kenyans each beat Haile Gebrselassie’s sanctioned world record of 2:03:59.

But Mutai’s mark is unlikely to be recognized as a world record because the IAAF requires courses to start and finish near the same point to discourage downhill, wind-aided runs. Boston starts at an elevation of 475 feet and finishes 16 feet above sea level; the wind at the start on Monday was announced at 21 mph, and it came in from the west — a tailwind.

Track’s international governing body has deemed the oldest and most prestigious marathon in the world — long considered one of the most difficult, too — to be too easy.