LOUIS REES-ZAMMIT has emerged as a fitness doubt for the Kansas City Chiefs’ pre-season game against the Detroit Lions.

Former Wales and Gloucester wing Rees-Zammit is targeting a place in the Chiefs’ 53-man roster for the NFL season, which they begin by tackling the Baltimore Ravens on September 6.

But the 23-year-old missed training on Wednesday, with the Chiefs assistant coach Dave Toub telling reporters Rees-Zammit might not be available for Saturday’s clash and confirming a back injury.