Midfielder heads back to the Stadium of Light following month at The VicNeale Cooper has confirmed that today's game at Crewe Alexandra was Craig Lynch's last with the Club.
The midfielder's month-long loan spell with Pools ends today and Cooper has revealed he will now return to Sunderland.
"I'd like to thank Sunderland for letting Craig come and spend a month with us," Cooper said.
"In an ideal world, I would like to have kept him longer but financially we have to do things right and at the moment it's just a bit difficult.
"He's had a good month here though, I hope he has enjoyed it and we wish him well for the future."
Lynch scored one goal in five appearances during his time at Victoria Park.