The former Melbourne player was appointed St Kilda's ruck coach last week.

Despite the new job being part-time, Doyle is unable to continue as Chargers' coach.

Chargers regional manager Mark Smart said the club had been aware in mid-December of Doyle's possible exit and created a succession plan.

Smart said the Chargers expected to offer the position to an "internal person" but were unable to confirm that person's appointment until today.

"We are 95per cent sure who the coach will be. It will cause minimal disruption because this person knows the club and the players."

Smart said the appointment with the Saints was a great step for Doyle.

"That was part of Greg's decision. He wanted to make sure he caused as little disruption as possible. It's a fantastic opportunity for him."

Last week the Chargers returned to preseason training with about 90 boys in the Chargers' program.

Smart said that number would be cut to about 60 in the coming weeks as the club prepares for intra-club matches before its preseason games.

Doyle played for both St Kilda (1990) and Melbourne (1992-96) in the AFL and has extensive coaching experience, having held development roles with the Oakleigh Chargers and Victorian Metro.

Doyle took over as Chargers coach before last season. He was assistant coach from 2005 to 2008 and Vic Metro under-18 assistant coach in 2009-10.

Doyle joins Aaron Hamill (offensive), Max Hudghton (defensive) and Troy Schwarze (midfield) in coaching roles.