After winning the Swiss league title with Aarau in 1992–1993, he joined Serie A team Lazio where he played under managers Dino Zoff and Zdeněk Zeman.

[4] Born in Switzerland to Italian parents, he was capped 34 times for Italy, scoring two goals, and played in UEFA Euro 1996 and the 1998 FIFA World Cup.

[8] Di Matteo became a regular starting-11 member of the Lazio side in midfield under managers Dino Zoff and later Zdeněk Zeman, and he made his debut for the Italy national team during his three seasons with the Rome club.

[9] Under Zeman, he was frequently deployed in the central midfield role, in which he was required to aid the team defensively – thanks to his formation as a sweeper during his youth –[9][10][11] as well as offensively and creatively.

[citation needed] Within 42 seconds of the kick-off of the final against Middlesbrough, Di Matteo scored the opening goal from 30 yards and Chelsea won 2–0.

[citation needed] Di Matteo played in midfield next to Gus Poyet, Dennis Wise and Dan Petrescu in the 1998–99 season as Chelsea finished third.

[citation needed] In a dour match, Di Matteo capitalised on an error by Aston Villa goalkeeper David James to score the winner in the 72nd minute, handing Chelsea their fourth major trophy in three years.

[19] Early into the 2000–01 season, Di Matteo sustained a triple leg fracture in a UEFA Cup tie against Swiss side St. Gallen and did not play for the next eighteen months.

Di Matteo was also capable of playing in a more offensive midfield roles, due to his ability to make forward surging runs, as well as his accurate long–range shot.

[27] On 26 November that year, Di Matteo took former Chelsea teammate and Norwegian international striker Tore André Flo out of retirement by signing him on a contract until the end of the season.

[31] In his first season, the team finished second in the Championship, behind Newcastle United, and won automatic promotion to the Premier League on 10 April with three games remaining after defeating Doncaster Rovers 3–2.

[32] On the opening day of the 2010–11 Premier League season on 14 August 2010, Di Matteo paid a return visit to Stamford Bridge as head coach of West Bromwich Albion.

[40] Di Matteo started his stewardship of Chelsea in winning form, with victories over Birmingham City, in a fifth round FA Cup match; Stoke City in a Premier League fixture; and Napoli in the last 16 second leg match in the UEFA Champions League, winning 4–1 to overturn the deficit in the first leg which Villas-Boas' Chelsea had lost 3–1.

[41] Di Matteo continued his form with Chelsea, by beating Tottenham Hotspur in the FA Cup semi-final 5–1 at Wembley and Benfica in the Champions League quarter-finals.

[44] On 19 May 2012, Di Matteo guided Chelsea to victory in the 2012 UEFA Champions League Final, defeating Bayern Munich at the Allianz Arena.

[47] On 13 June 2012, Chelsea announced that Di Matteo had been appointed manager and first-team coach on a permanent basis signing a two-year contract with the club.

[48] Chief executive Ron Gourlay said: 'Although he (Di Matteo) has set the bar very high in the short time he has been in charge, we know that Roberto is the right man to lead Chelsea onto further success.'

[58] Di Matteo had lasted just eight months as manager of Chelsea despite winning two major trophies, causing the decision to be controversial with many pundits and club fans.

[72] On 2 June 2016, Di Matteo was appointed the manager of newly relegated Championship club Aston Villa, working under the new chairman Tony Xia and Keith Wyness.