His second battle on 28 August 1820, was with Ned Brown at Wimbledon Common, and he won in fifteen rounds, earning a name for himself in the English ring.

[1] He defeated the younger boxer Cooper, the "Gypsey" on 25 May 1822 in seven rounds taking 22 minutes in Epson Downs, England, and though he fought carefully he had greater science throughout.

[4] Curtis won his first match with the larger and two inch taller Peter Warren the same year on 23 July, in ten rounds at Colnbrook, England.

In the final round, Curtis unleashed a left to the nose and a right to the jaw, and finished with a right to the eye, that ended the match, leaving his opponent struggling to remain conscious.

[5] In two matches that were critical in establishing his reputation, Curtis defeated the well known boxer Peter Warren on 16 April 1823 in Moulsey Hurst, and on 8 July 1823 in Blindlow Heath in one round.

Curtis vanquished Aaron in fifty minutes on a specially constructed stage in Andover, England, 70 miles East of London.

Though Aaron stood to profit from the £100 purse, Curtis was a threatening opponent, and though slightly shorter, he was an accomplished boxer, two years younger, and had easily defeated the skilled and larger Peter Warren in a previous contest.

In the ninth round, only fifty minutes into the contest, Curtis floored Aaron with a blow that reflected "his whole force", on Barney's throat knocking him out and ending the match.

[1][15] At the height of his popularity on 25 January 1828, Curtis performed an exhibition at Liverpool's Royal Amphitheatre with English champion Jem Ward, Jewish lightweight Young Dutch Sam, and Ned Stockman.

[16] Curtis' lone defeat came at the hands of Jack Perkins of Oxford on 30 December 1828, when he lost on a foul at the Parish Meadow at Henley Bottom in an eleven round match, around thirty-four miles from London.

Curtis had been sorely tested in the eighth through the eleventh rounds, and he could not return to scratch after the blow to his temple in the twelfth, and had his seconds end the bout in only 24 minutes.

The death of William Phelps eventually led to the adoption of the London Prize Ring Rules which included certain safety measures, and excluded some of the harsher forms of fighting by making them fouls.

It is not unlikely the Marquess and other nobleman were occasionally in the company of Curtis when he turned to drinking after his loss to Jack Perkins, and after his incarceration after the death of William Phelps.