David Moyes’ men found themselves 1-0 down at the Stadium of Light in the fifth minute when Craig Gardner fired home.
But on his first Premier League start, 18-year-old Adnan Januzaj powered in Patrice Evra’s cut-back, before sealing the win with a stunning volley in a six-minute second-half spell.
The win was just United’s third league victory of the season, but defender Jones believes the Red Devils showcased their title credentials with their attitude.
“Everyone dug in today, it was a great performance and a massive three points,” Jones told MUTV.
“We were put on the back foot right from the first minute, and perhaps we didn’t get out of the traps as well as we should have done.
“They were fired up, and perhaps we didn’t expect it quite as much as we should have in the first 10 minutes, but once we got to grips with the game I thought we played some terrific stuff.
“That was the sign of champions out there. When your backs are against the wall and everyone’s raising questions, a performance like that puts the record straight.”
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