The Giants are now 1-9 in season openers vs. Dallas, including 1-7 in Dallas. The Giants lost season openers there in 2013, 2015, and 2017, and won in 2016.
Spurred by a 59-yard run from Saquon Barkley on their second offensive play, the Giants went 91 yards in 7 plays on their first possession, with Eli Manning hitting Evan Engram for a 1-yard touchdown.
That was about the only good thing that happened all day for the Giants.
After an opening drive punt, Dallas scored touchdowns on five straight possessions. None of those scoring drives went for fewer than 75 yards. The Cowboys led after three quarters, 35-10.
With no pressure applied by a non-existent Giants pass rush, Dallas quarterback Dak Prescott did what he wanted.
Dallas totaled 495 yards of offense. Prescott finished 25-of-32 with 405 yards passing, four touchdowns and a perfect 158.3 passer rating.
Eli Manning completed 30-of-44 passes for 306 yards. Daniel Jones finished up. He played one series in the final two minutes and went 3-of-4 for 17 yards and lost a fumble while scrambling.
Barkley surpassed 100 yards rushing, carrying 11 times for 120 yards. He caught four passes for 19 more yards.
Tight end Evan Engram caught 11 passes for 116 yards and a touchdown.
The Giants had 470 yards of total offense of their own, but were never really competitive after their early surge.
The Giants (0-1) will play their home opener when they host the Buffalo Bills at MetLife Stadium next Sunday at 1 p.m. ET. Buffalo is 1-0 after coming back from a 16-0 deficit to beat the New York Jets, 17-16, on Sunday.