In July 2007, Welliton moved to Russian club Spartak Moscow, signing a five-year contract.

[16] In the next match against Krylia Sovetov Samara, Welliton was a subject of racism by opposition fans, telling him to go home.

[22] Former Russia midfielder Aleksandr Mostovoi heaped praise on the young striker after his performance in a 3–0 away win, stating "He has overcome all problems with passage into a new country.

He is young, fast, technical, an ideal artist who acts along the entire front line of attack, not just along the flanks as this past season.

[28] Later in the 2009 season, Welliton helped Spartak Moscow early to a prime position to qualify for the UEFA Champions League after finishing a dismal 8th place in 2008.

[30] However, he was sidelined for three weeks after injuring his ligaments of the ankle joint of the left leg during a match against Metallurg Lipetsk in the fifth round of Russian Cup.

[33] Because of this, Welliton's performance attracted interest from clubs around Europe, including La Liga side RCD Mallorca.

After making his return, Welliton then scored four goals between 26 June 2011 and 8 July 2011 before adding another on 28 August 2011 against CSKA Moscow.

[48] After returning from suspension, Welliton continued to suffer injuries when he hurt his back in late-October[49] and fractured his collarbone after colliding with CSKA Moscow's player Vasili Berezutski during a match on 19 March 2012, which saw him sidelined for the rest of the season.

[51] But Welliton's injury problem haunted him once again when he injured his thigh during the match against Terek Grozny, sidelining him for weeks.

[52] Welliton was left out of the squad and eventually fell out with Unai Emery due to lack of effort in training and performance.

[58] Welliton made his Grêmio debut on 14 February 2013, coming on as a substitute for Eduardo Vargas in the 73rd minute, in a 2–1 loss against Huachipato in group stage of Copa Libertadores.

[59] On 26 May 2013, Welliton made his league debut in the opening game of the season, coming on as a substitute for Hernán Barcos, in a 2–0 win over Náutico.

[66] After making 19 appearances and scoring four times, the club was keen to sign him permanently, but eventually decided against over the price tag.

[69] His time at Celta Viga was forgettable, as Welliton made only one appearance, coming on as a substitute in the 87th minute against Elche.

[73] After being on the bench for the first two matches, Welliton made his Mersin İdmanyurdu debut as a substitute in a 2–0 win over Çaykur Rizespor on 20 September 2014.

[74] Four days later, Welliton scored his first goal for the club, in the second round of Turkish Cup, in a 3–0 win over Kemer Tekirovaspor.

[75] On 8 November 2014, Welliton scored his first league goal for the club, in a 2–1 win over Balıkesirspor,[76] followed by his second in the next game two weeks later against Akhisar Belediyespor.

[87] Following Mersin İdmanyurdu relegation to the TFF First League, Welliton's future was in doubt, as his contract was due to expire on 30 June 2016.

[96] Despite missing out the remaining league matches of the 2016–17 season, Welliton went on to make thirty–four appearances and scoring twenty–five times in all competitions.

[97] On 26 September 2017, Welliton moved to UAE Pro-League side Sharjah, signing a two–year contract for 1.5 million Euros.

[98] Welliton made his Sharjah FC debut on 30 September 2017, where he came on as a substitute for Omar Jumaa during the second half, in a 2–1 loss against Al-Wasl.

[100] Welliton scored two goals in two matches between 30 November 2017 and 8 December 2017 against Al Jazira and Dibba Al-Fujairah Club.

[102] After returning to the first team, Welliton scored two more goals, including against Dibba Al-Fujairah Club in the last game of the season.

[107] However, later in the 2018–19 season, Welliton's goalscoring form soon dropped, scoring four times, leading Sebastián Tagliabúe leap over him as the league's top scorer.

Born and raised in Conceição do Araguaia, Brazil,[2] Welliton grew up in poor family and has two older brother and a younger sister.