Conor McGregor (green) has posted a sparring video on his 'thenotoriousmma' instagram. Is he already in training for a rumoured fight with Floyd Mayweather Jr? Conor McGregor (green) has posted a sparring video on his 'thenotoriousmma' instagram. Is he already in training for a rumoured fight with Floyd Mayweather Jr?

UFC star Conor McGregor has displayed his boxing skills in a sparring session as speculation builds over a future fight with Floyd Mayweather.

A McGregor-Mayweather fight could be edging closer after the American admitted last month he was most likely to make his comeback against the UFC's lightweight champion.

The Irishman is used to fighting in an MMA octagon, but has expressed his desire to test his punching power against Mayweather inside a ring.

He is well known for his explosive knockouts in the UFC and has vowed to inflict the first defeat on the multi-weight world champion.

Mayweather has suggested he will come out of retirement to face McGregor

The 39-year-old Mayweather called time on his hugely successful career after extending his unbeaten record to 49 victories with a unanimous points win over Andre Berto in September 2015.

But the sport's former pound-for-pound No 1, nicknamed 'Money', has suggested he will return for a lucrative showdown with McGregor.

Click on the video above to see Conor McGregor's sparring session.