The keeper was expected to depart Fratton Park this summer even before the loan arrival of Josh Griffiths from West Brom – and has now sealed his exit.
Exeter and Crawley had been among those to have shown interest in the 24-year-old who was once on the radar of Crystal Palace.
However, it was Sunderland which this evening emerged as his destination, with Bass signing a three-year deal after joining for an undisclosed fee.
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He will now compete with first-team regular Anthony Patterson to be the Black Cats’ first-choice keeper, yet, for the time being, will once again find himself as back-up.
The Academy graduate made 41 appearances during his time at Fratton Park and was in goal for the play-off semi-final elimination to Oxford United in July 2020 under Kenny Jackett.
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