Bell was hit on his chin while hitting throwdowns and needed stitches suggesting that the cricketer is unlikely to be a part of the playing XI in the first ODI against West Indies.
Bell, who replaced Kevin Pietersen in the One-day side following the latter's retirement from limited overs format recently.
Having replaced Pietersen in the side, England's coach had said he expects Bell to be himself than trying to play like Pietersen.
"We don't want him to do a similar job to Pietersen," said Flower. "We want him to be Ian Bell and play great international cricket."
Incidently Bell and Pietersen had both made their debut for England in ODIs in the same match against Zimbabwe in November 2004. Though he has been quite a good player, he is unable to cement his place in the squad after playing 108 ODIs.
While England's ODI captain also admitted that Bell was a doubtful starter for the first ODI agianst Windies, but he would decide the playing XI only at the toss as the opening batsman gets some more time to prove his fitness having replaced Pietersen in the One-day side.
"Ian Bell got hit in the nets today and has got a gash on his chin," Cook said on Friday.
"It is a concern, because he didn't look in a good way when he walked off.
"There was quite a lot of blood, and he has had stitches."
"We will have to play it by ear," added Cook of Bell's possible replacement.
"We'll announce the team at the toss like we normally do, we'll just have to play that one by ear," said Cook.
He also added that Ravi Bopara could be promoted up the order, from his likely number four spot.
On the other hand, Darren Sammy also expressed sympathy on hearing Bell's injury, as he said, "I don't think any cricketer wants to see an opposing player get injured, or will take pleasure in that. It is unfortunate for him."