The main rival of Manchester United is Manchester City. but the manager of Manchester United, Sir Alex Ferguson is rivals with the manager of Chelsea, Jose Murinho.
United's main rivals are Sheffield Wednesday FC(Pigs), who play at Hillsborough.
Other main rivals include local Yorkshire sides Leeds United, Rotherham, Barnsley, and Chesterfield.
Westham's main rivals are Millwall. Also they are mostly rivals with other teams in London including Arsenal, Chelsea and Tottenham.
Bradford City outside premier league inside Man utd or chelsea they just have a random hatred of chelsea also they have a rivalry with huddersfield
Manchester United
Most likely Liverpool
Manchester city
Millwall.
Arsenal is Tottenham Hotspur's main rival.
Tottenham Hotspur, Chelsea, Fulham, West Ham United and Manchester United
Lamborghini is the main rival for Ferrari.
Their main rival is Manchester United
The name of Edison's main rival was Nikola Tesla.
The main rival of FC Schalke is Borussia Dortmund.
Manchester United or Chelsea.. Always changes Manchester Utd and Chelsea are their biggest competition, but their true rival is tottenham
Chargers
England is Australia's main rival at the World Championships and Commonwealth Games.
The main rival now is Alabama. Following that would be Auburn.
Spain was their main adversary
Saints