The evergreen midfielder has signed up for the 2021-22 campaign with non-league Nuneaton Borough.
And he yesterday skippered the Southern League Premier Division Central members in their first pre-season friendly against Halesowen Town.
Baker made 46 appearances and scored nine times for Pompey when they claimed the League Two title in May 2017.
The former Coventry midfielder finished that season with a flurry of goals, netting in two of the Blues’ last three matches as they edged Plymouth to capture the crown.
He remained for the start of the following campaign, yet departed by mutual consent in August 2017 at the age of 34, following discussions with new boss Kenny Jackett.
Baker totalled 50 matches for the Blues and would later join Indian side ATK, Coventry and Brackley.
Now in his second spell with Nuneaton, he netted as Jimmy Ginnelly’s side drew 2-2 in yesterday’s opening friendly in front of a crowd of 257.
Baker, who also represented Southport, Morecambe, Stockport, Coventry and MK Dons in his long career, turns 39 in December.
The ex-Blues skipper was last month appointed assistant head coach to Ian Burchnall at Notts County.
However, the 39-year-old will remain registered with the National League side should he be required in emergencies.
Doyle, who totalled 97 appearances and three goals during two Fratton Park seasons, celebrates his 40th birthday next month.
A message from the Editor, Mark Waldron
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