Tried-and-tested troops who they have the utmost trust in and have delivered success in the past means reunions are fairly frequent in football.
Just look at former Pompey boss Harry Redknapp with Peter Crouch and Niko Kranjcar, for example.
Look at when Paul Cook arrived at Fratton Park in the summer of 2015 and ensured Gary Roberts followed him from Chesterfield.
It’s a recruitment policy that Danny Cowley could also look to implement during his Blues summer overhaul.
In truth, it wouldn’t be a surprise if any of his former players from his time managing Lincoln and Huddersfield who’re available join him.
Cowley’s put the free agent market to good use so far, swooping for Clark Robertson (Rotherham), Shaun Williams (Millwall) and Ryan Tunnicliffe (Luton).
But who are some of the head coach’s ex-troops currently without a club and he could be tempted to move for.
We’ve taken a look...
5. Alex Pritchard
The attacking midfielder was limited to 12 appearances under Cowley at Huddersfield duo to injuries. However, the head coach called Pritchard after he left the Terriers. The former England international could be a solution to fill the vacant number-10 role at Pompey but wouldn't be cheap. Photo: James Chance
6. Bruno Andrade
Pompey had the Portuguese on trial from Boreham Wood before Cowley signed him for Lincoln ona permanent deal in 2018. Andrade helped the Imps clinch the League Two crown that season before he was sold to money-spinning Salford the following January. Never quite got going in Greater Manchester and was released at the end of last season. Photo: Lewis Storey
7. Tommy Elphick
The former Aston Villa defender was a regular under Cowley at Huddersfield before he suffered cruciate ligament damage to his right knee in November 2019. Elphick didn't play for the Terriers after that before he was released at the end of last season, but he did return to action for their B team. If the 33-year-old is fully fit, he could provide plenty of nous in defence. Photo: Nathan Stirk
8. Elias Kachunga
The DR Congo international was part of the Terriers side that got promoted into the Premier League in 2018. Kachunga scored three goals in 32 games when Huddersfield stayed up in the Championship but was released after Cowley's axing. The German-born forward spent last season at Sheffield Wednesday, however, was deemed surplus to requirements after they dropped to League One. Photo: Naomi Baker