Tyson Fury looks laser-focused as he releases training footage three weeks out from his undisputed heavyweight showdown with Oleksandr Usyk... and declares he 'wishes it was tonight!'

Tyson Fury is looking locked in for his heavyweight showdown with Oleksandr Usyk after releasing training footage just three weeks out from their fight.

Fury and Usyk will finally face each other for the right to be called the undisputed heavyweight champion of the world in Riyadh, Saudi Arabia on May 18.

They were due to meet in February but the fight was postponed after Fury suffered a cut in sparring. However, that delay may have helped the Gypsy King as he appeared laser-focused in the gym in the video he posted on Instagram on Saturday morning.

In the clip, Fury is seen with his eyes fixed on the imaginary target as he shadow boxes inside the ring.

The WBC champion looks light on his feet as he dances around the ring, repeatedly practicing his jab and head movement.

Many expect Fury to be on the front foot against Usyk, who is widely regarded as one of the best pure boxers in the sport.

The short clip indicated that this is likely to be the case, as Fury used his footwork to move forward, but his consistent jab suggested he will aim to work his way into range methodically rather than recklessly lunging in.

The video ended with Fury shaking his arms out and hyping himself up as he looked in good spirits with fight night fast approaching.

Alongside the footage, a caption read: '3 weeks today guys, wish it was tonight!'

Fury is eager to get back into the ring after a disappointing showing in his last fight against Francis Ngannou.

The 35-year-old Brit was expected to ease to victory against the former UFC champion who was making his professional boxing debut.

But Ngannou knocked Fury down in the third round, and was unfortunate in the eyes of some observers to end up on the wrong side of a split decision.

Ngannou then faced Anthony Joshua last month, but suffered a devastating loss as he was knocked out cold in the second round.

Having watched his fellow Brit make far easier work of Ngannou than he did, Fury will want to make amends next month, but he has his work cut out against the undefeated Usyk.

Usyk holds wins over Joshua (twice), Daniel Dubois, Derek Chisora and Tony Bellew in his career, and will be hoping to beat a fifth British opponent to cement his place as the best heavyweight on the planet.