Jordan Tansey made 24 Super League appearances for Hull FC last season
Hull FC full-back Jordan Tansey's long-term future with the club looks in doubt after he was dropped again for disciplinary reasons.
It is is the third time in a year that the ex-Leeds player, 24, has been omitted for off-the-field behaviour.
He was warned about his conduct last season, after being left out of games against Harlequins and Hull KR.
"Jordan was left out for disciplinary reasons, not for the first time," Agar told BBC Radio Humberside.
"It is something we're going to have to address over the next week.
"We'll deal with it through the proper and right channels.
"Obviously there are some adjustments Jordan needs to make if he wants to be a professional rugby league player.
"I'm disappointed at having to make these late changes but Jordan has let us down."
Tansey, who joined Hull from Leeds on a two-year deal in June 2009, was handed warnings for his previous misdemeanours.
On the field, Joe Westerman scored the match-winning try on his Hull debut against his former club as Agar's men beat the Tigers 22-20 in their final warm-up before the start of the new Super League season.
Hull FC's first game is the Magic Weekend 'local derby game' against city rivals Hull KR at the Millennium Stadium on 13 February.
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