Rio Ferdinand's decision to become a professional boxer at the age of 38 will probably still have a few people scratching their heads.

After enjoying a stellar career as one of the best defenders to play for England over the last few decades, many critics see it as little more than a publicity stunt.

But anyone who follows Ferdinand on Instagram will already know how seriously he is taking it, with various exercises and workouts regularly being posted on social media.

Given his footballing background, there's a good chance Rio might still possess a few of the basic fitness elements required to be successful in the ring.

However, that will count for nothing if he can't actually box.

Before the former Man United star can make his boxing debut he must be granted a licence by the British Boxing Board of Control.

That will only happen if Ferdinand can pass an assessment which will judge whether he is actually good enough to compete.

Should it all go well, Rio's first fight could well be in 2018.

But before all that, Ferdinand was back in the BT studio on Tuesday night to cast his verdict on Liverpool's Champions League tie against Spartak Moscow.

And given it was the first time Gary Lineker has worked alongside boxing's newest star, he couldn't help but throw a couple of 'jabs' in Rio's direction.

It started before kick-off when the pair briefly discussed Ferdinand's career change at the start of the programme.

But arguably the best comment Lineker made came after the 1-1 draw in Russia.

Ferdinand's defence was down when the much-loved presenter asked him if Liverpool's hopes of qualifying for the round of last 16 'would go the distance'.

That brought a wry smile from Rio, who claimed that, despite Jurgen Klopp's men drawing their first two games, they should still qualify from the group.

Lineker hadn't finished yet, though, and cheekily responded: "Yeah at this stage it's just sparring isn't it?"

Skip to 7:50 in the video below:

Luckily Ferdinand saw the funny side of his colleague's sly remarks.

But he might have to get used to a few more boxing phrases being thrown in his direction over the course of the season.