The club also participated in the UEFA Champions League as a result of finishing second in the Primeira Liga in the previous season.

After José Antonio Camacho led Benfica to second place, the club offered him a new two-year contract as manager in June.

As a condition to renewing the contract, Camacho requested that the club sign more established players, but budget restraints allowed for limited investment.

Because their second-place finish only granted a berth in the third qualifying round of the UEFA Champions League, Benfica had to play Lazio for a spot in the group stage.

They improved in subsequent games, but dropped points two more times, including at the official opening of the new Estádio da Luz.

In the final two months, Benfica unexpectedly recovered six points against Sporting, overtaking them to finish second and qualify for the 2004–05 UEFA Champions League.

In the aftermath of their best league finish since 1997–98, Benfica negotiated a one-year extension to Camacho's contract, which had been set to expire on 30 June.

[1] As a condition to agreeing to stay, he wanted several problems related to the technical staff, training fields and signings to be solved.

[3] In his presentation, he confessed that the club's limited finances would make it harder to sign players; he also said that Benfica would give their best but did not expect to dethrone Porto.

[6][7] The club also looked into strengthen their options at centre and at left-back, negotiating unsuccessfully with Ânderson Polga, Atouba and Júnior.

[1] After a week and a half of training sessions on Jerez de la Frontera, they travelled to Nyon on 16 July, for a seven-day tour.

This reduced their hopes of reaching the group stage of the Champions League, as Camacho said: "Lazio were supposed to do more tonight to win this game.

[26][27] On the following Saturday, Benfica defeated Vitória de Guimarães at home, in a 2–0 win, which Camacho admitted to be flattering in comparison with the team performance.

[31] Because of the financial loss from the elimination, the club was unable to invest further in squad; the team closed the transfer window with only Alex and Luisão as new signings.

[34] Despite leading the game with 90 minutes played, Benfica allowed the visitors to score two goals in extra time to draw the match 3–3.

"[38][39] Three days later, Benfica started their UEFA Cup campaign against La Louvière, a Belgian team that António Simões described as "easy".

[47] They dominated the match, and only a strong performance from Silvio Proto allowed the Belgians to leave with only a goal conceded.

[51] Camacho acknowledged that Benfica struggled after conceding Gil Vicente's goal, adding that it was a normal behaviour in football.

[62] Camacho attributed the result to the excessive number of games in short amount of time, something most of the players were not accustomed to.

[74] The following Wednesday, Benfica progressed through the fifth round of the Portuguese Cup, with Luisão scoring a single goal in an away win against Académica.

Sporting added a second before half-time and closed the match with another converted penalty; winning 3–1 and increasing their lead over Benfica to four points.

[79] On 11 January, Benfica visited União de Leiria at the newly developed Estádio Dr. Magalhães Pessoa.

[83] At the press conference, Camacho criticized the media's behaviour after two weeks of intense pressure due to previous results.

[85] They won the game with a late goal, but the match was more remembered for the collapse and later death of Miklós Fehér, who suffered a cardiac arrhythmia brought on by hypertrophic cardiomyopathy.

[99] While both teams had opportunities to open the score sheet in the first half, the winning goal arrived on the 61st minute when Zahovic released a powerful shot.

[101] Although Sporting had a seven-point advantage, Camacho refused to admit defeat on the Champions League race, saying: "We have not lost the fight yet.".

[85] With the team resting players for the game with Inter, Camacho brought in Nuno Gomes and the striker scored the winning goal with 15 minutes left to play.

[118] The win, Benfica's largest there since 1989-90, helped them reduce the gap to second place to three points, because of Sporting's loss to Boavista.

Davide reduced the lead on the 86th minute, but an additional goal by Miguel led to a 3–1 win that put Benfica in second place in the league table, after catching up to Sporting.

Note 2: Players with squad numbers marked ‡ joined the club during the 2003–04 season via transfer, with more details in the following section.