This is one man who needs no introduction! Diego is a player whose style of play can bring some genuine extravagance to the field of play. Unmatchable dribbling, stunning passing and even goals from 62 meters out are all synonymous with the Brazilian.  The former Werder Bremen man controls the game from the midfield, acting as tact-giver and creative inspiration. A player of his calibre can prove invaluable to his side.

Santos
At age six, Diego started to show his talent when training with Comercial FC in Ribeirão Preto. Diego was first signed by the São Paulo team Santos FC at the age of 12.

Porto
Diego was then signed by Portuguese club FC Porto in July 2004 as a replacement for the FC Barcelona-bound Deco and was seen as his successor to Deco. On 30 October 2004, Diego scored his first goal for Porto in a 2–2 draw against Nacional. In his first season at Porto, Diego made 30 appearances, scoring two goals against Sporting Clube de Portugal and Sporting de Braga. In 2005–06, however, Diego did not maintain a stable place in the Porto team under coach Co Adriaanse and also found life difficult at Porto. He eventually left Porto for Werder Bremen.

Werder Bremen
In May 2006, Diego signed a contract with Werder Bremen until 2010 for a transfer fee of €6 million. His first match for Werder Bremen came in the DFB-Ligapokal (League Cup). Werder Bremen won the cup, beating Bayern Munich in the final on 5 August.   In October 2006, he won a second Player of the Month award and again in December 2006. He was then named as the Best Player of the first half of the Bundesliga.

On 15 April, Diego again played well, scoring in the 2–0 win over Borussia Dortmund. After the 2006–07 season ended, Diego won the Bundesliga Player of the Season award organised by popular magazine kicker. He received just over 50 percent of the votes. Unfortunately, his team did not win the Bundesliga after finishing third in the table, behind champions VfB Stuttgart and Schalke 04.

Diego started 2007-2008 season well, scoring a penalty on the first matchday. Diego gave many outstanding performances. He was crucial as Bremen got through to the Champions League's group phase. Diego was voted Player of the Month in September.  Diego's last season in Werder Bremen was his most successful with 20 goals in total. In his last match with Bremen, Diego gave the assist to Mesut Özil's winning goal against Bayer Leverkusen in the German Cup final, to win the German Cup for the sixth time.

Juventus
On 26 May 2009, Diego signed a five-year contract to join Juventus at the end of the season. The fee paid to Bremen by Juventus was worth €24.5 million. The price can rise by a further €2.5 million in case of the fulfillment of established sports objectives in the next five years. Diego made his Juventus debut against the Korean side Seongnam, in a game they won 3–0.

Wolfsburg
Eventually, on 27 August 2010, Diego moved from Juventus to VfL Wolfsburg for a club record transfer fee of €15.5 million, which Juve would only received €14.75 million as 5% of the transfer fee transferred to his youth clubs as solidarity contribution. In his first match for VfL Wolfsburg, he scored his debut goal in a game which Wolfsburg lost 3–4 to Mainz.

Loan to Atlético Madrid
After the 2010–11 season at Wolfsburg, new manager Felix Magath told Diego in May he had no future with Wolfsburg. On the last day of the transfer season, Diego joined Atlético Madrid in La Liga on a season-long loan. On 10 September 2011, he made his debut for Atlético against Valencia CF.

Return to Wolfsburg
Diego returned to Wolfsburg following the end of his loan spell in Madrid. Diego played his first game for the club in a 1–0 victory over Stuttgart on the opening game of the Bundesliga. He netted a brace in Wolfsburg's 3–1 defeat of Bayer Leverkusen on 11 November, bringing to an end Bayer's 11-game unbeaten run and giving Wolfsburg it's first home win of the Bundesliga season.