[2] Belasco used Mendoza's new scientific style of "boxing", which included careful parrying of opponent's blows with a fist or arm, a technique borrowed from the sport of fencing.

Like most successful boxers of his era, he adopted the stance recommended by Mendoza's Art of Boxing, a slight slouch with fists raised to allow both a quick jab with one arm and a ready block of oncoming punches with the other.

Belasco, though he was thirty years younger, engaged Mendoza in a sparring partnership in an exhibition in 1818, one of which took place the first week of December in Lincoln, Lincolnshire, in the East Midlands, around 150 miles North of London.

[2] His first match of note was with the better known English boxer Josh Hudson near the barge house at Woolrich, and Belasco, according to Puglistica, the leading boxing journal of the era, won the contest after one hour and thirty minutes.

In the final round, Payne ran at Belasco furiously and was floored for the last time by a solid punch, ending the match after seventeen minutes when the Butcher could not resume the battle.

[10][4] On 23 July 1817, at Moulsey Heath, Pierce Egan wrote that Belasco was defeated by Tom Reynolds, a potato-salesman from Armagh, Ireland, after fighting a remarkable sixty-six rounds for one hour and twenty minutes.

Belasco lost to his greatest adversary, Jack Randall, an incomparable English champion, on 30 September 1817, at Shepperton Range, Surrey, 15 miles southwest of London, for the substantial sum of 50 guineas a side.

Randall dominated the second round, drawing first blood with a blow to the mouth, and in the fourth turned the tide with a powerful left that penetrated Belasco's guard, putting him quickly down.

In a masterfully fought scientific match that drew great interest from the public, Randall faithfully worked Belaso's body before finally tasting victory after 54 minutes in the sixth.

After dominating Belasco, Bell's Life in London wrote of Randall that "His hitting and getting away, his style of stopping and returning, with the excellent judgment he manifested, added to his activity and quickness on his legs, all tended to stamp him as one of the most finished boxers of his weight.

[2] On Tuesday, 22 February 1819 he met Phil Sampson at Potter's Street in Essex for a more substantial 50 guineas a side, but the fight ended in an argument or wrangle, though Belasco collected the purse.

Both the third fight, a gloved affair, at the Tennis Court in Windmill street, London, on 21 December 1820, and the fourth on 25 August 1823, which was fought on Crawley Downs in Sussex, ended in the defeat of Belasco.

Criticized for their brutish behavior and appearances, and said to "have gone about yelling and hooting in a fashion calculated to thoroughly disgust all whom it failed to terrify", Belasco and his followers were referred in a letter to the English newspaper the Liverpool Albion as "the lowest class of Jews in the east of London", and condemned for injuring the cause for which they marched.

Though he won by a large margin, receiving 6792 votes, Rothschild would not be allowed to serve in Commons without taking a vow as a Christian upon a New Testament, which as a Jew, he refused to do.

As late as 1 April 1830, he was charged with assaulting a Black man, Thomas Rastall at Bow-Street in London with a poker and required to appear in court.

[22] In fact, in September 1834, he was tried and convicted of "keeping a house of ill-fame" by the Middlesex Sessions, and sentenced to two years imprisonment, though the length of time he served is unknown.

[23] In late March 1834, his wife Leah had been convicted of keeping a brothel at Leg Alley in the Parish of St. Paul, but was required to serve only one year.

[25] As late as 1854, Belasco was still working as proprietor of the Sun and Star public house, on London's Pettycoat Lane, but likely due to problems with the law his license was not renewed in the Spring of 1858.

[26][27] In descending steps, he sank lower in the social order until, continually brought into conflict with the officers of the law, he lost all his friends, and died in nearly abject poverty in London, on 13 May 1859.