He lifted back-to-back FA Cups as a Magpies player in the early 1950s alongside greats including Joe Harvey and Jackie Milburn.
Known as the ‘Rock of Tyneside’, he was cool-headed, tough and steady, forming a terrific bond with United supporters over the course of a decade.
Fast for a big man, he signed for United from Airdrieonians in 1946 and was a key figure in the heart of the defence as the Magpies won promotion back to Division One in 1948.
Brennan relished a duel with the big-name centre forwards of the day, more often than not coming out on top and was in the fans’ eyes the king-pin of United’s defence.
He played in both the 1951 and 1952 FA Cup Final triumphs at Wembley against Blackpool and Arsenal respectively and during his time on Tyneside, he won seven caps for Scotland - too few in many observers' eyes.
While his on-field achievements had already propelled him into Geordie folklore, it was the popular Scot’s sad departure from the club following an infamous dispute with the club’s hierarchy in 1955 that truly set his story apart.
Almost 60 years on from Brennan being controversially dropped for the 1955 FA Cup Final and his subsequent forced departure from St. James’ Park, his family made an emotional return to St. James' Park with the BBC to celebrate his life and immense contribution to the club in 2014.