Erling Haaland was joined on the pitch by a former world champion boxer after putting Manchester City in front against Sheffield United on Sunday.

Haaland had endured a frustrating first half at Bramall Lane after he missed a penalty for the first time since joining City, but he made no mistake when he got another chance after the break, heading home Jack Grealish's cross from close range.

He did not appear to be in the mood to celebrate his goal initially, clearly still annoyed at his earlier penalty miss, but was then joined on the pitch by an over-eager fan.

Appearing out of nowhere, a supporter jumped on Haaland's back and planted a kiss on his cheek, and it has since been revealed that the fan in question was ex-world champion Terry Flanagan.

Flanagan held the WBO lightweight title between 2015 and 2017, making four successful defenses of the belt before moving up in weight.

The Manchester southpaw won his first 33 professional fights but suffered consecutive defeats against American duo Maurice Hooker and Regis Prograis in 2018.

He went on to have three further fights - winning them all - to end his career with a 36-2 record.

The 34-year-old now appears to be spending his spare time watching his beloved City, and could not resist the temptation to celebrate with Haaland this weekend.

Flanagan was beaming from ear to ear as he embraced Haaland. The Norwegian striker initially appeared unaware of who had jumped on him but patted Flanagan on the head after realizing it was a City fan.

Stewards then raced on to get Flanagan off the pitch as Haaland was congratulated by his teammates.

Flanagan may have thought he was celebrating the winning goal, as City finally took the lead after failing to find a breakthrough in the opening hour.

However, the Blades hit back through Jayden Bogle to set up a nervy finish.

City responded like true champions, though, as Rodri fired home a late winner to maintain their 100 percent start to the season and send them back to the top of the table.