The Argentina star riled the red half of Manchester when he quit United in July 2009 for their local rivals, but he is not the first player to switch sides.
Tevez will be eager to make an impact this weekend, both for his own satisfaction and because ambitious City are just five points and two places behind table-topping United.
Here, Sportsmail takes a look at five players who crossed the Manchester divide.
Peter Schmeichel The Great Dane kept 22 clean sheets for United in 1992-93 and was crowned 'World's Best Goalkeeper' two years running.
The 6ft 4in stopper left Old Trafford after nine years in 1999, having helped the club to the Treble, and later joined City for the 2002-03 season.
He was never on the losing side in a Manchester derby.
Legend: Peter Schmeichel had plenty of reason to celebrate at Manchester United - and later he joined rivals City
Denis Law The Scotland striker was a record British signing at City for ?55,000 from Huddersfield in 1960, and after a season in Italy, set a new record for more than twice that figure at United.
'The King' laid down the law there for 11 years, with the Red Devils twice winning the first division, before he left for City in 1973.
But when his famous goal for City at Old Trafford appeared to have caused United's relegation, he avoided celebrating.
WATCH DENIS LAW'S FAMOUS GOAL FOR CITY AGAINST UNITED
Brian Kidd City assistant manager Kidd held precisely that position at Old Trafford 20 years ago, crossing over as a player too.
The Mancunian goal machine started out at United, scoring in their European Cup final win over Benfica on his 19th birthday, and spent three years at City following a spell at Arsenal.
The boomerang Kidd then helped Sir Alex Ferguson scoop a plethora of titles before managing Blackburn and having spells with Leeds, England, Sheffield United and Portsmouth. He returned to City in 1999.
Crossing the divide: Brian Kidd playing for United (left) and in his current role as assistant manager of City (right)
Billy Meredith The Welsh wizard joined City in 1894, scoring their only goal in the 1904 FA Cup win over Bolton.
When they failed to support him during a bribes scandal, he spilled the beans over the club's financial practices, forcing them to sell their best men.
He and several others were bought cheaply by United, where he assisted in founding the Players' Union and winning numerous titles, before rounding off his colourful career back at City.
Andy ColeCole joined United from Newcastle in 1995 for five successful years, netting 187 Premier League goals and winning five titles, two FA Cups and the Champions League.
The striker formed a brilliant partnership with Dwight Yorke and was key to United's 1999 Treble triumph.
Cole signed for City on a free in the summer of 2005. Injury blighted his season, however, and he headed for Portsmouth after just one term, his best years behind him.
Manchester legend Denis Law: It's the 60s all over again with City challenging United to be kings of England Manchester City race up Europe's rich list, but United remain wealthiestMay insists he never meant to taunt City after being forced to cancel eventDavid Silva can fire us to derby glory! City captain Tevez hails team-mate Let them boo me! Tevez relishing Old Trafford return as City striker eyes winAll the latest Manchester United news, features and opinionAll the latest Manchester City news, features and opinion
Explore more:People: Alex Ferguson, Brian Kidd, Andy Cole, Denis Law, Dwight Yorke, Carlos Tevez Places: Newcastle, Leeds, Manchester, Argentina, Scotland, Italy, United Kingdom