Updated

Two of the Team USA runners in the men's marathon have dropped out of the race in the early going Sunday morning at the Summer Olympics.

Ryan Hall, the fastest American marathoner ever, stepped off the course roughly 54 minutes into the marathon and appeared to be grabbing his right hamstring, just below his butt cheek. Hall had been battling plantar fasciiitis since the fall. Then just seconds later, teammate Abdihakem Abdirahman withdrew, seemingly favoring his right foot.

Neither of the two runners, who now receive a "DNF," were in medal contention. At the 15k checkpoint, shortly after the race leader Kenyan Wilson Kipsang Kiprotich upped the pace, Abdi was 1:10 back and Hall was in 50th place, 1:59 off the lead.

Their withdrawals leave Meb Keflezighi, who at at 37 is the oldest member of Team USA, as the only American still on the course. He was 39 seconds back at the 15k point, and and then 1:03 behind Kipsang at the 20k mark.

For Hall, who ran a truly-world class 2:06:17 in the 2008 London Marathon (a different course than Sunday), the fastest time ever by an American, it's an extremely disappointing result.