American needs more work insists Tigers boss.
The sprightly forward returned to his parent club Villarreal last week after his season long loan on Humberside was cut short following a three match ban for headbutting Sunderland’s Alan Hutton.
The American arrived in the Premier League with big promise, but failed to make the impact Hull were looking for in their fight against relegation.
The 20-year-old notched just one goal in 28 appearances during his time in English football, but the former New York Red Bulls star became a cult hero at the KC Stadium.
"The fans have been fantastic, given him great support and probably he hasn't fulfilled his potential here,” Dowie admitted to a press conference.
“He's got one goal and for the level of investment it's probably not enough.”
Hull are thought to have an option to be able to purchase the striker for a fee of around £6 million, but with the club Championship bound and struggling financially the option seems unlikely to be taken.
Dowie though has been impressed with Altidore yet believes he needs to improve in training if he's to become a top player.
"I've spoken to Jozy [Altidore] a number of times since I've been here and, if Jozy can train the way he plays, I think he's got a great opportunity but he needs to understand that it's day in, day out,” added Dowie.
“He's a lovely, laid-back boy and there's no bad side to him but he needs to focus on training at a better level. You've got to stretch yourself every day in training."
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