New boy Niko Muir netted his first goal in Hartlepool United colours but Pools were robbed of their first pre-season win by Benjamin Kimpioka's last gasp strike.
Former Hendon striker Muir, plying his trade in the Isthmian League last season, capitalised on an error by Sunderland defender Donald Love to dink home the only goal of the game.
And after a refreshingly solid defensive show, Pools' copybook was blotted with virtually the last kick of the game as Black Cats' youngster Kimpioka cracked home from 25 yards.
Pools boss Bates was delighted with his players' show.
"It was a good run out against a very good team," said Bates.
"It was the exact opposite to the Billingham game, where we had most of the possession.
"I was really pleased with the performance - particularly the shape and formation. I think it worked really well.
"Defensively, I thought, for the first 60 minutes, we coped well with what they threw at us.
"There were lots of positives to take from that game, despite the late goal. Overall I was very pleased."
Bates again went with an experimental three at the back with Andrew Davies in the centre, Myles Anderson to the left and Carl Magnay again on the right.
Further forward former SAFC man Liam Noble sat in midfield, supported by Conor Newton with Josh Hawkes and Ryan Donaldson providing chief support to Muir up top.
And despite a bright opening from the visitors it was Pools who drew first blood.
Love, attempting to find debuntant keeper Jon McLaughlin, played his back pass short and Muir, showing his goalscoring instinct, pounced, beating the Scotland international to the ball by before teasing over the onrushing stopper for 1-0.
Rather than retreat into their shell, Pools continued to cause problems for Jack Ross' men.
Mark Kitching fired over from six yards after a pinpoint Josh Hawkes cross while Kenton Richardson's control let him down when he looked set to trouble McLaughlin in the visiting goal.
After the break it was much of the same.
While Sunderland created the odd opening - the best of which fell to Josh Maja, who saw an effort tipped wide by Scott Loach, and Callum McManaman, who skewed wide from 18 yards - they struggled to create clear cut openings.
Comfortable, even after changing 10 of their players on the hour, Pools looked certain to see the game out but for youth sensation Kimpioka popping up and conjuring some late magic to restore some face for Sunderland and former Poolie Ross, whose side opened up pre-season with a 1-0 loss to Darlington.