Sportsmail can reveal the 34-year old took exception to having former Burnley goalkeeping coach Phil Hughes thrust on him at the expense of his mentor Fred Barber. He then stunned Coyle by presenting him with an ultimatum.
Jaaskelainen was barely half-an-hour into his first training session with Hughes when he called a halt and told Coyle he wanted Barber reinstated.
Demands: No1 Jussi Jaaskelainen insisted coach Fred Barber was his job back
It is understood the former Finland No 1 was ready to demand a move, had the manager not relented.
Headache: Coyle now has two goalkeeper coaches
Coyle had already told Barber to leave after deciding to bring in his own backroom staff from Burnley, but was forced to ask him to return.
Barber accepted and is now listed alongside Hughes as joint-goalkeeping coach on Bolton's official website.
Bizarrely, Hughes still takes his place on the bench on matchdays, but Barber has regained control of day-to day training.
Jaaskelainen's trust in Barber's coaching skills has grown steadily during a long-standing relationship, and he was horrified at hearing Coyle was dispensing with the old guard.
The unwanted distraction could explain the keeper's uncharacteristic uncertainty of late, with some blame being attached to him for at least two of Arsenal's goals at the Emirates on Wednesday night.
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