[5][6][7] Saunders won his first 49 amateur fights at senior level, including the 2007 Commonwealth Championships[8] and the 2008 Strandzha Cup, edging out Cuban Carlos Banteux.

[14] Saunders went on to score wins against Norbert Szekeres, Gary Boulden and Tony Hill, the last of these giving him his seventh professional knockout victory and his first major regional title, the Commonwealth middleweight championship, on 28 April 2012.

This turned out to be one of Saunders's first tough outings, as he was forced to go the full twelve rounds en route to a competitive unanimous decision victory on the judges' scorecards.

[16] A pair of trouble-free fights came next, against tough slugger Matthew Hall on 21 March 2013 and Gary O'Sullivan on 20 July, both of which also lasted twelve full rounds.

Having secured his third defence of the British middleweight title, Saunders earned the Lonsdale Belt outright; he gave this to his father Tommy as a Christmas present.

In February 2015, Saunders and Warren accepted a 'step-aside' financial offer from promoter Lou DiBella in order for Lee to face Peter Quillin instead.

At around the same time, due to his high ranking, Saunders also received an offer from the IBF to fight for their vacant world middleweight title, but he reiterated his intention to follow the WBO route.

[28] On 19 December, Saunders defeated WBO middleweight champion Andy Lee via majority decision to capture his first world title, with judges' scores of 114–112, 115–111, and 113–113.

[30] On 8 July, Saunders revealed that he would be fighting on 17 September, likely on the undercard of Canelo Álvarez vs. Liam Smith at AT&T Stadium in Arlington, Texas, which would have been broadcast on HBO pay-per-view in the US.

[31] However, Golden Boy Promotions vice president Eric Gomez told ESPN on 14 August that Saunders would no longer feature on the undercard due to him rejecting all of the opponents presented to him.

[42] On 28 February, it was announced that Khurtsidze would fight undefeated British boxer Tommy Langford for the vacant interim WBO title in April.

[70] On 16 October, Lemieux's manager Camille Estephan stated the negotiations were going well for the fight and could possibly take place at the Bell Centre in Canada on 16 December 2017.

A few names listed as Saunders' potential opponents were Martin Murray, Conrad Cummings, Rafael Bejaran and Jason Quigley.

[77] Two days later, it was confirmed that 4-time world title challenger Murray (36-4-1, 17 KOs) would be Saunders next opponent, with the fight being billed as 'Battle of Britain' on BT Sport.

[78][79] On 20 March, Saunders suffered a hand injury in training forcing the card to be cancelled, however the fight was quickly rescheduled for 23 June 2018 at the same arena.

[85] On 12 July, the WBO ordered Saunders to make a mandatory defence against former two-time light-middleweight champion Demetrius Andrade (25-0, 16 KOs), with both sides having 10 days to reach a deal.

Hearn stated he would wait to see if the Massachusetts commission will allow Saunders to fight, however confirmed Andrade would still appear in the main event, whether it be a vacant world title or a non-title bout.

[103] On 18 February, Warren announced that Saunders would be moving up in weight and challenging for the vacant WBO super-middleweight title at the SSE Arena in London on 13 April.

[104] A week later, Gilberto Ramírez stated although he was scheduled to fight at the light heavyweight limit for his next bout, he had not vacated his super-middleweight title.

[108] On 25 March, at a press conference, Saunders vs. Isufi (27-3-2, 20 KOs) was announced to take place for the interim WBO super-middleweight title on 18 May at Stevenage's Lamex Stadium.

Saunders won the fight by a landslide unanimous decision, winning the WBO super-middleweight title and becoming a two weight world champion.

[115] In September 2019, it was announced that Saunders would make the first defence of his WBO super-middleweight title and his US debut on the KSI vs. Logan Paul II undercard.

[127] Behind closed doors, in a one-sided fight, Saunders dominated Murray with a convincing lopsided unanimous decision victory, with the judges' scorecards reading 120–109, 120–109, 118–110 in his favour.

The bout was postponed due to the spread of the Coronavirus disease, while Canelo's team floated the possibility of a Golovkin trilogy late in 2020 that might conflict with the Saunders fight.

[134] With 73,126 fans in attendance at AT&T Stadium in Arlington, Texas, a record amount for an indoor boxing event in the US, Saunders was hit with an uppercut towards the end of the eighth round, causing immediate swelling to his right eye.

"[139] A video of Saunders in his Rolls-Royce taunting a drug addict, offering £150 of crack cocaine to perform a sex act or punch a passer-by, was released on 17 September 2018.

The General Secretary of the British Boxing Board of Control (BBBofC), Robert Smith, responded: "I have just seen the videos and I can tell you we find it disgusting.

[142] In March 2020, Saunders was alleged to have made a phone call to Delta Airlines claiming that three other boxers on a flight from Las Vegas to New York were infected with COVID-19.

[143][144] Later in March, Saunders posted an online video instructing men how to hit their female partners whilst in isolation due to the coronavirus pandemic.

[151] Saunders released a statement days later via his Instagram account, labelling the accusations as "complete rubbish" while also saying that he would "make no public comment at this stage" acting on the advice of his lawyer.