Courtesy of Instagram/@MrDavidHaye

David Haye has upped the ante over his on-again, off-again domestic heavyweight fight with Tyson Fury, posting a video purportedly showing him signing a contract to face his rival on September 28.

In the video, which Haye posted to Instagram on Monday, the former WBA world champion appeared to sign a fight contract, adding that he would post it to Fury to add his signature and confirm the eagerly anticipated bout.

In previous negotiations Fury had complained about purse splits, a stumbling block that had seemingly caused the fight to be called off. But it seems some of the figures have been adjusted to accommodate Fury's demands.

"We've re-jigged the contract so he's nice and happy," Haye said, before adding his signature. "All done."

Posting the video, he commented: "I've just signed to fight Fury on Sep 28, let's hope he finally agrees (and signs today) and he doesn't keep delaying."

If Fury does sign the contract, it will confirm undoubtedly the biggest domestic fight of 2013.

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