The former Blues captain passed away over the weekend at the age of 65 after a long illness.
The defender arrived at Fratton Park from Coventry in 1975 and went on to become a popular figure with supporters in his three years at the club, making 115 appearances and scoring two goals.
Cahill captained England Schoolboys after coming through the ranks at his hometown club but went on to Highfield Road in 1973.
He was signed by Ian St John in a wretched time for the club with Pompey finishing rock bottom of Division Two in his first full campaign.
Things went downhill from there with a 20th-place finish in the third tier followed by a drop into the basement division in 1979, after finishing bottom of the table.
Cahill’s form was a bright spot in that period with his no-nonsense style of play endearing him to the Fratton faithful.
After leaving Pompey in 1979, Cahill went to play for Tranmere, Stockport and a number of clubs in America including San Jose Earthquakes.
Pompey stalwart and football historian, Barry Harris, remembers Cahill as a no-nonsense player who endeared himself to supporters.
Harris said: ‘Paul came here just short of his 20th birthday and went on to become a real fans’ favourite.
‘He wasn’t that elegant but gave his all and the supporters really liked him for that.
‘He captained the England youth team but lost his way at Liverpool and then Coventry, before Ian St John picked him up.
‘Paul was a sound player and he was very passionate and so pleased when he was made skipper.
‘He’d been ill for a while and will be missed by all who remember him, because he was such a nice man. It’s a sad loss.’
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