After his debut season at Hertha, he soon signed for Hamburger SV and established himself as an integral part of the team, helping the club reach two consecutive UEFA Europa League semi-finals.

Boateng started his career with the youth team of Tennis Borussia Berlin, before joining Hertha BSC in 2002.

[10] In the 2009–10 season, he broke into the Germany national side after impressing for Hamburg, earning himself a place in the squad for the 2010 FIFA World Cup.

[12] He made his City debut in a pre-season friendly against Valencia for the first half, alternating between centre-back and right-back with Micah Richards.

[13] During the week prior to the start of the 2010–11 Premier League season, Boateng suffered an injury setback on international duty with Germany during a friendly against Denmark.

[17] On 14 July 2011, Bayern confirmed the transfer of Boateng to the German club for a fee of €13.5 million on a four-year deal.

[18] His Bundesliga debut for Bayern came in a 0–1 home defeat against Borussia Mönchengladbach, on 6 August; an error between himself and fellow new signing goalkeeper Manuel Neuer allowed Igor de Camargo to score the only goal.

[19] The team finished the season as runners-up in the Bundesliga, DFB-Pokal and Champions League, with Boateng playing the finals of the latter two tournaments in their entirety.

[21] He scored his first Bundesliga goal with a header from Phillip Lahm's cross on 9 March 2013, the winner as Bayern came from behind for a 3–2 home win against Fortuna Düsseldorf.

[7][24] On 2 October 2013, Boateng picked up a red card against former club Manchester City which resulted in a one-match ban in the Champions League.

[39] On 11 March 2017, Boateng made his return after 108 days as a substitute by replacing Javi Martínez in the 64th minute in a 3–0 victory over Eintracht Frankfurt.

[40] On 14 April 2017, head coach Carlo Ancelotti confirmed that Boateng was ruled out of the away match in the league against Bayer Leverkusen due to adductor problem.

[41] He made his return on 20 May 2017, Boateng sustained muscle injury and was subbed off just after 11 minutes in the last match of the season where Bayern won 4–1 against SC Freiburg.

[43] On 13 September 2017, Boateng made his comeback after 115 days on the sidelines in the Champions League match and provided one assist to Joshua Kimmich's late goal after being subbed on in a 3–0 victory over Anderlecht.

[44] On 21 December, Boateng scored a header in a 2–1 win as his side knocked their fierce rival Borussia Dortmund out of the DFB-Pokal during the round of 16 match.

[47] On 11 April, Boateng and his teammate Thomas Müller made their 100th European appearance in the Champions League match against Sevilla as the game finished 0–0 draw.

[52] Boateng lost his place in the starting lineup as Bayern's coach, Niko Kovač, decided that Hummels and Süle were his first option.

On 3 November 2020, Boateng scored his first goal of the season in a 6–2 away win over Red Bull Salzburg in the Champions League.

[57] In April 2021, Bayern's sporting director Hasan Salihamidžić stated that Boateng's contract would expire in the summer and would not be extended.

[citation needed] Boateng was included in Joachim Löw's final 23-man squad for the 2010 World Cup in South Africa.

[69] Boateng started his second straight game as Germany beat England 4–1,[70] and Argentina 4–0 in the quarter-final,[71] as well as the 1–0 loss to Spain in the semi-final.

[77] He played a central role in Germany's victory in the final, winning 83% of his duels[78] and making several good tackles alongside teammate Mats Hummels, while only committing 1 foul throughout the entire 120 minutes.

[85] On 23 June, Boateng was sent off after receiving a second yellow card during their second group stage match against Sweden, which Germany won 2–1.

[88] On 5 March 2019, national team coach Joachim Löw confirmed that he would plan without Boateng for the foreseeable future, along with his club teammates Mats Hummels and Thomas Müller.

Physically strong and composed in possession, he has gained a reputation as a tough-tackling defender, with good passing and an ability to read the game.

Despite his talent in his youth, he was initially accused by certain pundits of being error-prone defensively; however, he later came to be considered one of the world's best players in his position.

[105] On 10 February, one week after the confirmed breakup, Lenhardt was found dead in an apartment in Berlin, with investigators believing the cause of death to be suicide.

[109] On 9 September 2021, in a German court in Munich, Boateng was found guilty of assaulting his ex-girlfriend, Sherin Senler, while on holiday in the Caribbean in 2018 and was sentenced to 60 days (daily fine in lieu of jail time, calculated from the rate of income).

[100][110] The Munich District Court imposed the highest possible financial damages for the domestic violence conviction on Boateng, who had denied the allegations of abuse.