Kejelcha dug deep and crossed the line in 3 hours 47min 1sec, taking 1.44 seconds off the previous record set by Morocco's Hicham El Guerrouj in 1997.

The two-time world indoor 3,000 metre champion's time is also an outright Ethiopian record, bettering the outdoor mark of 3:48.60 set by Aman Wote.

It was third time lucky for the 21-year-old, having narrowly missed out on breaking world indoor records in his two previous races.

He finished just 0.01 seconds outside the mile record at last month's Millrose Games in New York City, clocking 3:48.46, and was then beaten to the 1,500m record at the International Association of Athletics Federations (IAAF) World Indoor Tour event in Birmingham when compatriot Samuel Tefera won in 3:31.04.

In Boston, Kejelcha had set himself the target of breaking the world indoor records for both the 1,500m and the mile in the same race.

The Alberto Salazar-coached runner followed three different pacemakers for the opening laps and passed through 809m in 1:52.

Worried the pace was not quick enough, Kejelcha moved past the final pacemaker about two minutes into the race and was then out in front alone.

He was inside 2:51 with two laps remaining and kept up his swift pace for the last 400m.

The clock had already ticked over to 3:31 by the time he passed the 1,500m checkpoint, but Kejelcha would have to wait until after the race to find out his split with his immediate concern being to reach the finish line of the mile.

Having completed the event, his split was confirmed at 3:31.25, making him the third-fastest indoor performer in history behind Tefera and El Guerrouj.

Home favourite Johnny Gregorek finished second in 3:49.98, moving to sixth on the world indoor all-time list, just 0.09 seconds shy of Bernard Lagat's North American indoor record.

Completing the top three was fellow American Sam Prakel in 3:50.94.

The Bruce Lehane Invitational was held at the Boston University Track and Tennis Center.