Ahead of Monday's eager awaited Premier League clash between Man United and Chelsea, we take a closer look at how the two managers shape up.
WHO ARE THEY?
David Moyes: aged 50, born April 25, 1963, Glasgow.
Former defender for Celtic and Preston, among others, before turning player-manager with North End and then moving to Everton and subsequently to Manchester United.
Jose Mourinho: aged 50, born January 26, 1963, Setubal, Portugal.
Midfielder with a host of low-ranking Portuguese teams turned manager with the Midas touch with Porto, Chelsea, Inter Milan and Real Madrid.
Moyes: After four years at Preston, who he took from the brink of the fourth tier to narrowly miss promotion the top-flight, moved to Goodison Park for 11 years at Everton, where he transformed the Toffees from mid-table men to perennial European challengers.
His talents were recognised by Sir Alex Ferguson, who nominated his fellow Glaswegian as his successor.
Mourinho: Spent time absorbing the knowledge of others, including Sir Bobby Robson, before first embarking on a management career with Benfica in 2000.
Enjoyed successful short spells in Portugal, England, Italy and Spain - where he led Real Madrid to the Primera Division title ahead of Pep Guardiola's Barcelona - before returning 'home' to Chelsea in the summer.
Moyes: Produces sides in his own image. Made the Toffees a solid, often potent, force.
His teams are workmanlike team, with versatile and physically strong players.
His Everton side featured a number of ex-Manchester United players. Now he can shape a United of his own.
Mourinho: Teams characterised as well-organised, indomitable and physical, epitomised by the Chelsea team of 2005 to 2007 which had a spine of Petr Cech, John Terry, Frank Lampard and Didier Drogba.
At Real Madrid there was a similar core, with the athletic Cristiano Ronaldo as the attacking focal point.
Moyes: Cut from the same cloth as his predecessor, Ferguson.
A Glaswegian, with a fiery temperament at times, he works relentlessly and slept in his car while taking the opportunity to learn from other coaches at the 1998 World Cup.
Mourinho: Full of charisma, exudes confidence and has a tendency to implode when things do not go his way, such as when he poked Guardiola's assistant Tito Vilanova in the eye during a technical area spat.
Takes the spotlight from his players and appears to thrive by causing chaos.
Moyes: Manchester United: Community Shield (2013)
Mourinho: Porto: Primeira Liga (2003, 2004); Portuguese Cup (2003); UEFA Cup (2003); Champions League (2004).
Chelsea: Premier League (2005, 2006); League Cup (2005, 2007); FA Cup (2007).
Inter Milan: Serie A (2009, 2010); Italian Cup (2010); Champions League (2010)
Real Madrid: Primera Division (2012); Copa del Rey (2011).