Nathan Thompson is in the frame for half a century of Pompey outings.
The right-back will make his 50th appearance for the club should he feature in Saturday’s trip to AFC Wimbledon.
Thompson became Kenny Jackett’s first Blues signing in June 2017, arriving on a free transfer from Swindon.
He was also on Pompey predecessor Paul Cook’s radar, before the League Two title-winning boss moved to manage Wigan.
Injury-permitting, Thompson has been an automatic choice for Jackett at right-back, with spells as a holding midfielder and at centre-half as well.
The 27-year-old is currently a booking away from a one-game suspension, following four yellow cards in his past eight appearances.
A combative character, he has totalled 13 bookings and two red cards so far in his Fratton Park career.