|Full name||Guilherme Madalena Siqueira|
|Date of birth||28 April 1986|
|Place of birth||Biguaçu, Brazil|
|Height||1.83 m (6 ft 0 in)|
|Playing position||Left back|
|2004||→ Avaí (loan)|
|2006||→ Lazio (loan)|
|2008–2009||→ Ancona (loan)||24||(1)|
|2013–||→ Benfica (loan)||15||(1)|
|* Senior club appearances and goals counted for the domestic league only and correct as of 20 September 2013.
† Appearances (Goals).
At age 18, Siqueira was signed by Internazionale from Ipatinga in August 2004, at first in temporary deal for €125,000. He also played for hometown clubs Figueirense (his first club) and Avaí before joining Inter.
On 11 August 2006, he joined Udinese in a co-ownership deal, for €750,000. Siqueira never became a regular for Udinese and made 3 starts and 13 substitute appearances in the 2006–07 season. He made his Serie A debut on 10 September 2006 in a 1-0 loss to Messina. During the 2007–08 season Siqueira remained at Udinese but was seldom used. As Udinese did not buy full ownership from Internazionale, the out of favor Siqueira was loaned to Ancona to join another Inter owned player, Rincón. During the 2008-09 season with Ancona Siqueira featured regularly for the newly promoted club making 24 league appearances and scoring his first professional goal.
In June 2009, he returned to Udinese as the club now had Siqueira's entire registration rights. On 10 January 2010, he substituted Paolo Sammarco in the 71st minute, his first match of the season. He then made 2 more substitute appearances for the club.
In 2010 Siqueira joined Granada on loan as part of a partnership agreement with Udinese in which various players joined Granada from the Italian club. In his first season in Spain Siqueira featured regularly for his new club and helped Granada gain promotion to the First Division. After a fine first season with Granada, on 30 June 2011 he penned a four-year contract to remain with the club, as his contract with Udinese expired.
On 20 March 2012, he scored an audacious meisteresque dink from the penalty spot against Barcelona in the league at the Camp Nou. On the very last minutes of the transfer deadline day, Siqueira signed a season-long loan deal with Benfica, with an option to make the move permanent for €7 million.
- FC Internazionale Milano SpA Report and Accounts on 30 June 2005 (Italian)
- "INTER SIGN THREE YOUNG PLAYERS". inter.it. 26 August 2004. Retrieved 2010-01-10.
- "RELATÓRIO DE TRANSFERÊNCIAS INTERNACIONAIS EM 2004" (in Portuguese). CBF. 11 March 2005. Retrieved 2010-01-10.[dead link]
- "CESAR JOINS INTER". inter.it. 31 January 2006. Retrieved 2010-01-10.
- "SIQUEIRA JOINS UDINESE". inter.it. 11 August 2006. Retrieved 2010-01-10.
- Crediti — Compartiecipazioni ex art.102bis NOIF, FC Internazionale Milano 2006–07 bilancio (Report and Accounts), Require Purchase in CCIAA (Italian)
- "Transfer market: co-ownership deals". inter.it. 26 June 2009. Retrieved 2010-01-10.
- Video on YouTube
- "Benfica take Siqueira on loan from Granada". FIFA. 3 September 2013.
- "Granada's Guilherme Siqueira joins Benfica on loan". skysports.com. September 3, 2013.
- Granada official profile (Spanish)
- BDFutbol profile
- Transfermarkt profile
- Profile at La Gazzetta dello Sport (Italian)