Alex Henery missed wide left on a 60-yard attempt with 9 seconds left in the second quarter.
DeMeco Ryans intercepted a poor pass by Romo and returned it 36 yards to the Cowboys 30 to set up Henery's 31-yard field goal that cut it to 10-3.
But the Cowboys answered with Romo tossing a 9-yard TD pass to Terrance Williams to make it 17-3.
At Oregon, Kelly's teams scored 150 points in three meetings against Monte Kiffin when he was defensive coordinator for USC. Kiffin now holds that position with the Cowboys, so the defensive mastermind wins their first matchup in the pros.
NOTES: The Cowboys got their first road win and are 3-0 in the division for first time since 2007. ... The Eagles were the fourth team in NFL history to have 400 yards of offense in each of first six games. They were held to 278.
Online: AP NFL site: http://pro32.ap.org/
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