•This was the second consecutive meeting between the two sides after the Americans beat Kenya 14-7 in the first leg.
•In the earlier match tries by Alvin Otieno and Johnstone Olindi were not enough as they fell to Australia in their opening match.
Kenya Sevens must beat Canada in their final pool match by 17 points if they harbour any hopes of advancing to the Dubai Sevens quarterfinals on Friday afternoon.
Innocent Simiyu's charges lost their opening two fixtures, going down 21-14 to Australia and 24-21 to the USA at the Sevens Stadium.
It was a gut-wrenching loss to the United States Eagles in their second match with Perry Baker scoring at the death with virtually the last passage of play which condemned Kenya to their second defeat.
This was the second consecutive meeting between the two sides after the Americans beat Kenya 14-7 in the first leg.
USA struck first with playmaker, Kevon Williams, changing direction to leave his markers well beaten to score at the centre for a converted try to lead 7-0.
USA speedster Carlin Isles was sent to the sin bin and from the resultant penalty, Herman Humwa forced his way to the try-line, scoring a converted try to level matters at 7-7.
Shujaa were now on the ascendancy and skipper Nelson Oyoo combined brilliantly to release veteran Billy Odhiambo to score at the centre. Johnstone Olindi converted to give Kenya a 14-7 lead at the interval.
On resumption, Mike Friday's charges came out firing on all cylinders and scored an unconverted try courtesy of Williams to narrow the deficit to 14-12.
The USA piled on the pressure and Steve Tomasin bulldozed his way for try, which was converted for a 19-14 lead.
Shujaa responded with a well-taken try as Oyoo fended off three tackles and passed the ball to Alvin Marube who dived over with Olindi converting for a 21-19 lead
Heartbreak was to follow for Kenya in the final seconds as Baker raced off a long kick-off to cross the line.
In the earlier match, tries by Alvin Otieno and Johnstone Olindi were not enough as they fell to Australia.