Mayweather's swansong fight receives lukewarm reception

American boxer Floyd Mayweather's purported finale bout appears to be heading towards a box-office flop as hundreds of tickets are reportedly still available less than 24 hours before his fight against challenger Andre Berto on Saturday.

This is viewed as a big setback for the unbeaten boxer as it has apparently failed to generate similar public interest, which was seen during the feverish build-up to May's showdown with Manny Pacquiao.

Mayweather was accused of picking an easy fight against Berto, who is rated by many pundits as a massive underdog, Sport24 reported.

The 38-year-old will equal former world heavyweight champion Rocky Marciano's record of 49-0 if he succeeds at the MGM Grand in Las Vegas.