After retiring as a player in 2017, Amorim began his coaching career at Casa Pia in 2018, before resigning that same year amid a dispute with the Portuguese Football Federation (FPF).

[10] In early October 2011, whilst on duty with the national team, Amorim criticised Jesus' preferences – Benfica played most of their games without a single Portuguese player.

[11] Increasingly disgusted with his plight, in December, he refused to train with the bench players – after warming up for several minutes only to not be used – following a game against Rio Ave, being subjected to the club's disciplinary proceedings;[12][13] on 30 January 2012, a loan was arranged with Braga until June of the following year.

[15] At the beginning of the following campaign, he featured the full 120 minutes to help his team defeat Rio Ave in the Supertaça Cândido de Oliveira, thus winning four titles in 2014.

[16] On 24 August, however, he got severely injured while playing on an artificial turf at Boavista,[17] with news the next day reporting an anterior cruciate ligament injury;[18] he was sidelined until 11 February 2015, when he featured as a substitute in a 3–0 home defeat of Vitória de Setúbal in the semi-finals of the domestic league cup.

[22] Amorim appeared for Portugal at the 2007 UEFA European Under-21 Championship in the Netherlands, as the national side eventually lost to Italy for the final berth for the following year's Summer Olympic Games.

[28] He made his debut in the tournament on 26 June in the last group phase match against Ghana, featuring the full 90 minutes in the 2–1 win but seeing his team eliminated on goal difference.

[29] Amorim's style was similar to countryman Tiago, with both playing the same position, operating in central midfield, both defensive and offensive, although he could also be deployed as a right-back or winger.

[42] Three months later, he replaced the dismissed Ricardo Sá Pinto at the helm of the first team on a two-and-a-half-year contract, with the Minhotos being eighth place in the league at the time of his appointment.

[45] In the Primeira Liga, on 15 February, Amorim recorded Braga's first win away to Benfica in 65 years, with João Palhinha scoring the game's only goal.

[51] In the rest of the games he took over, Amorim won six and drew three, but lost to Benfica in the Lisbon derby and rivals Porto at the end of the season, guiding Sporting to a fourth-place finish and qualification to the Europa League third qualifying round.

Along with the new signings, Amorim promoted Daniel Bragança, Gonçalo Inácio, Matheus Nunes, Nuno Mendes and Tiago Tomás to the first-team squad.

[59] In his second summer transfer window, Amorim identified the defensive areas which required improvement for the squad, with his options being shorter than Sporting's domestic rivals, leading Ricardo Esgaio to return to the club, midfielder Manuel Ugarte and defender Rúben Vinagre also being signed.

After remaining as a back-up to Antonio Adán, Luís Maximiano was sold to Spanish La Liga side Granada, which in turn led to Sporting signing João Virgínia.

[60][61] At the end of the transfer window, starting left-back Nuno Mendes was loaned to Paris Saint-Germain, with Pablo Sarabia moving in the other direction.

[66] On 3 December, he led his squad to their first victory at the Estádio da Luz in six years, following a 3–1 away defeat of rivals Benfica in the Lisbon derby.

[70] Sporting's success inevitably attracted richer clubs in Europe to their players, and the summer transfer window saw an exodus of key players: João Palhinha and Matheus Nunes to Premier League sides Fulham and Wolverhampton Wanderers, respectively, and Nuno Mendes completing a permanent move to Paris Saint-Germain, after a one-year loan spell.

[78] After losing 2–1 at home to Eintracht Frankfurt on 1 November, Sporting finished third in the group stage, which put them in the Europa League knockout round play-offs.

[80] Shortly after, the club also featured the departure of Pedro Porro to Tottenham Hotspur on 31 January 2023, the deadline day of the winter transfer window.

[81] In the Europa League, Amorim led Sporting to the quarter-finals, following a surprise victory over favourites Arsenal on penalties, after drawing 3–3 on aggregate in London.

After failing to qualify for the Champions League, he admitted that he put his position at risk, despite having the trust of the club's President, who labelled him as 'one of the best coaches in the world', citing the poor planning of the season, especially the departure of Matheus Nunes to Wolverhampton Wanderers as one of the factors for the failure of the objectives.

However, Amorim refused the offer, and ahead of an important league match with Porto, he publicly apologized for the trip, deeming it a mistake and that the timing was wrong.

[101][102][103] In his first match of the new season, on 3 August, Sporting suffered a 4–3 loss to rivals Porto in the 2024 Supertaça Cândido de Oliveira, despite leading the game by three goals.

[100][105] On 29 October, following the dismissal of Manchester United manager Erik ten Hag, Sporting confirmed that the English club were set to trigger Amorim's €10 million release clause.

[125] Exuding a positive outlook and a laid-back, conciliatory demeanor, Amorim has consistently emphasized that he refrains from engaging in discussions about referees with the media.

"[133][54] During his tenure with Sporting CP beginning in March 2020, Amorim primarily played a 3–4–3, a system he adopted during his tenure at Casa Pia and Braga, with two midfielders, usually João Palhinha and Matheus Nunes, and later, Morten Hjulmand and Hidemasa Morita in the following seasons, being responsible for protecting the defense, and emphasize the attacking capabilities of the wing-backs, like Pedro Porro and Nuno Mendes at first, and later Geny Catamo.

[54][135] They focus on exploiting the wings and half-spaces (with players like Pedro Gonçalves playing inside with Pablo Sarabia and Nuno Santos sticking to the left side of the attack).

[54][135] Amorim is often credited with rejuvenating Sporting CP by promoting young talents, instilling a winning mentality, and developing a versatile and cohesive style of play.

[138] In April 2023, Manchester United player and fellow compratriot Bruno Fernandes praised Amorim's management style, believing that his skill set is adaptable to leagues outside of Portugal and had all the qualities "to be able to succeed in English, French, or Spanish football".

[132] Amorim was described by Guillem Balagué of BBC Sport as a coach who's "still adding layers of knowledge to his methods but he still believes football only makes sense if those watching are thrilled by it".