The current West Brom winger hailed his former manager's techniques and ability and backed the Spaniard to turn things around at Goodison Park.
Former Wigan Athletic FA Cup-winner Callum McManaman has told the Liverpool Echo that Roberto Martinez's training methods and studious nature will enable him to turn Everton's underwhelming season around.
The Toffees are suffering another poor campaign after finishing 11th last year, and are currently mired in the bottom half of the table 11 points off a guaranteed Europa League spot.
Current West Brom man McManaman won the FA Cup under Martinez at the DW Stadium in 2013, although the Latics were relegated that season before the Spaniard left for Goodison Park.
Despite Everton's struggles, the 24-year-old, who grew up supporting the club in the Merseyside area, has said that his old boss has everything it takes to turn their fortunes around.
He told the Echo: "I will always back him up. I hope he can turn it round. I know Everton are conceding goals but some of the performances and goals we’ve scored this season have been great.
"Training wasn’t just about attacking under Roberto at Wigan. We worked on everything, there wasn’t anything we didn’t work on, we did defensive stuff. We did a lot of off the ball stuff.
"He would never a miss a session, he was always hands on and always there. He just always encouraged me to express myself and to go and enjoy it and do what I was good at. Roberto knew what I was good at and played to my strengths."
McManaman, who joined Wigan upon being released from the Everton academy at the age of 16, was a regular in Martinez's final season at the club, scoring six goals in 30 appearances in all competitions.
With Everton unlikely to mount a challenge to qualify for Europe via the Premier League, Martinez and McManaman will be hoping for a repeat of their cup success three years ago.
The Toffees host Chelsea in an FA Cup quarter-final at Goodison Park this weekend.