The 2nd pacemaker picked up the pace enough were a shot at 12:49i WR was possible but the pace dropped after 2nd rabbit Vincent Rono stopped pacing. Guess who chased Isiah all the way to the line in his 7:37 3000m win? Vincent Rono. So the 1st 1000m may have cost him a real shot at the WR since they had to pick up the pace so much with the 2nd rabbit.
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excerpt from online article:
Kipchoge helps push Koech
It was the second pacemaker Vincent Rono, who increased the pace during the 5000m in a way that even Kenenisa Bekele’s World record (12:49.60) suddenly was within reach. Rono dropped out of the race at the 3000m mark, which he had reached in 7:43.52. After that a duel developed between Kenyans Eliud Kipchoge and Isaiah Koech. It was another Koech, who was expected to challenge Kipchoge. But Paul Kipsiele Koech, who had broken the Düsseldorf meeting record a year ago with a time of 13:02.95, had lost contact before the 3km mark and later had to settle for third in 13:15.64.
Meanwhile at the front Koech and Kipchoge pushed each other. First it was Koech leading for a couple of laps. Then Kipchoge went to the front after around 3700 m. With 500 metres to go Koech tried to get past Kipchoge, but Kipchoge reacted and kept the lead. Not for long though. With one lap to go it was Koech who had taken the lead and stormed to an amazing time.
Only three of the most prominent long distance runners in history have run faster indoors: Besides the current World record holder Kenenisa Bekele these are Haile Gebrselassie (Ethiopia/12:50.38) and Daniel Komen (Kenya/12:51.48). Isaiah Koech clocked the fourth fastest time ever.
Kipchoge in second place, set a great personal best of 12:55.72, which now makes him the fifth fastest runner indoors.
Koech, who quickly disappeared into the warm-up area after the race and was not available for an interview, has most probably run his first ever indoor race on Friday. In 2009 he had won the 3000m gold medal at the World Youth Championships with 7:51.51. In 2010 he then placed fourth in the junior race of the World Cross Country Championships.