Natasha Jonas retains IBF title after split decision win over Mikaela Mayer

Natasha Jonas, left, was given a stern test before retaining her world title. Pic: Peter Byrne/PA

Natasha Jonas was pushed to the limit but retained her IBF welterweight crown with a razor-thin split decision victory over American rival Mikaela Mayer in a thriller in Liverpool.

Jonas started strongly in the first defence of the world title she won by defeating Kandi Wyatt last July but Mayer steadily grew into the bout and was the busier of the two in several riveting exchanges.