A full international since 2007, he has earned 24 caps and represented Brazil at the 2008 Olympics and 2011 Copa América, winning a bronze medal at the former.

[10] On 26 July 2007, he was officially unveiled as a Liverpool player for a fee of £5 million and was given international clearance to compete in the final of the Barclays Asia Trophy.

[11] By late November, manager Rafael Benítez gave Lucas his chance to start a game in the Liverpool midfield after easing him in during his first few months at the club.

[citation needed] The Brazilian got off to a good start with a well taken opening goal in a 2–1 friendly win over Swiss side Lucerne in July.

[14][15] Lucas returned with a bronze medal and Benítez had high hopes for the Brazilian's future, stating, "This season he will improve because he is a very, very good professional and has experience of the Olympic Games.

"[16] Lucas noted that Liverpool's squad was much improved from the previous season and relished the opportunity to compete for trophies, despite the increased difficulty of getting a first-team place.

"[20] Benítez also underlined Lucas' credentials, stating that he had been captain for both Grêmio and his national youth team, and that competing for place against Javier Mascherano, Steven Gerrard and Xabi Alonso was inherently difficult.

[23][24] On 14 March, Lucas played a key role [citation needed] in Liverpool's 4–1 victory over Manchester United at Old Trafford, starting in place of the injured Xabi Alonso.

Dirk Kuyt's header a minute later briefly gave Liverpool the lead, but Frank Lampard's 89th-minute strike leveled the score to 4–4, with Chelsea winning 7–5 on aggregate to go through to the semi-finals of the tournament.

This form earned praise from manager Rafael Benítez, and gained him a start against Tottenham Hotspur for the opening game of the 2009–10 season on 16 August.

[29] On 16 September 2010, Lucas scored his sixth goal for Liverpool shortly after replacing Ryan Babel in the club's first Europa League group stage match against Steaua București.

[39] In the initial run of games within the 2014–15 Premier League and other cup competitions, Lucas was rotated in and out of the squad, leading to speculation surrounding a move away from Anfield.

[44][45][46][47] Lucas was on the substitute bench on 22 March in a 2–1 defeat against Manchester United after coming back from a six-week injury layoff.

[49] Lucas made his 300th appearance for Liverpool on 26 January 2016 against Stoke City in the Football League Cup semi-final at Anfield.

[52] On 18 January 2017, Lucas scored his first goal for the club since 16 September 2010, a first-half header in the FA Cup 3rd round replay against Plymouth Argyle.

[56] Lucas made his official debut for the Rome club in a 3–2 win over league champions Juventus in the Supercoppa Italiana, on 13 August.

After missing out on the Brazil world cup squad in South Africa, Lucas played the full 90 minutes in a friendly against the United States on 10 August 2010.

[71] On 17 July 2011, Lucas was shown a straight red card in the 2011 Copa América play-off quarter final against Paraguay, after an extra time altercation with Antolín Alcaraz.