Simon Thorup Kjær (Danish pronunciation: [ˈsiː.mʊn ˈkʰjæːɐ̯]; born 26 March 1989) is a Danish former professional footballer who played as a centre-back.
Kjær was named 2007 Danish under-19 talent of the year and 2009 Danish Talent of the Year. He played 132 matches for Denmark, including participation at the FIFA World Cup in 2010, 2018 and 2022, and the UEFA European Championship in 2012, 2020 and 2024.
Born in Horsens, Kjær started playing football when he was four years old. This led him to join a small-time club, Lund IF near Horsens, before moving to the youth team of Danish Superliga club FC Midtjylland (FCM) in 2004, where his father, Jørn Kjær, was the club's equipment manager. He was one of the first players to graduate from FCM's football academy, the first of its kind in Denmark, coming through the system alongside Midtjylland teammates Jesper Weinkouff, Christian Sivebæk and former teammate, Winston Reid. Kjær started out playing in the midfield position before one of his coaches switched him to a defender position, a position he played until retirement. While at the club system, Kjær was named the best player of a French youth tournament in April 2006. This resulted in Midtjylland subsequently rejecting offers from Lille OSC for Kjær and Jesper Juelsgård.
Kjær made his senior debut for Midtjylland in the Viasat Cup training matches in June 2006, Two months later, he signed his first professional contract, keeping him until 2009. Kjær was promoted to the first team squad in January 2007. He had a successful trial with Real Madrid in August 2007, but their transfer offer was refused by FC Midtjylland. Soon after, Kjær signed a five-year contract with Midtjylland instead in September 2007.
Kjær made his Superliga debut on 30 September 2007, in the 2–0 victory against AGF By October 2007, his performances attracted the likes of Premier League clubs Middlesbrough and Chelsea. He went on to play three more matches in the first half of the Danish Superliga 2007–08 season. Kjær played all 15 games in the second half of the Superliga season, forming a defensive partnership with Magnus Troest. He kept three consecutive clean sheets between 29 March 2008 and 13 April 2008 against OB, Copenhagen and AaB.
In February 2008, Kjær signed a five-year contract with Italian club Palermo, effective from the summer 2008, earning Midtjylland a €4 million transfer fee. On 5 June 2008, he was presented at the club's press conference alongside new signing, Andrea Raggi.
However, his start to his Palermo's career suffered a setback when Kjær faced competitions in the club's defence, as well as, adapting in Italy. On 26 October 2008, he made his Palermo debut, coming on as a half-time substitute against Fiorentina in Serie A, as they lost 3–1. After the match, his performance was praised by the club. This was followed by making his first start for the club, as they drew 1–1 against Lecce three days later. Kjær scored his first goal for Palermo in his third appearance on 2 November 2008, as well as, setting up the club's first goal of the game, in a 3–0 win over Chievo. He has been involved in the first team, establishing himself in the starting eleven, playing in the centre-back position. Due to his physical strength and tenacity, Kjær's performance continued to improve and was named the second best player under 21 in Serie A by La Gazzetta dello Sport. It wasn't until 15 March 2009 when he scored his second goal of the season, in a 5–2 win against Lecce. Kjær then scored his third goal of the season, in a 4–1 win against Bologna on 19 April 2009. For his performance, he was named Serie A's Team of the Week. Kjær ended the 2008–09 season as the club's top scoring defender in Serie A with three goals in 27 appearances in all competitions.
Kjær confirmed his reputation as a first team regular in the 2009–10 season, and formed a strong defensive partnership with fellow centre-back Cesare Bovo. As a result, he signed an improved contract with the Sicilian club in September 2009. From the start of the 2009–10 season, Kjær started in every match until he missed one match, due to suspension. He returned to the starting line-up from suspension, playing the whole game, as Palermo lost 5–3 against Inter Milan on 29 October 2009. A week later on 8 November 2009, Kjær scored his first goal of the season, in a 3–1 loss against Bologna. He was named 2009 Danish Talent of the Year in November 2009, beating Arsenal's Nicklas Bendtner and Ajax's Christian Eriksen after his successful first season in Palermo. In January 2010, he was also named as Danish Footballer of the Year for 2009. The next day, Kjær celebrated with a goal against Cagliari that decided the match for Palermo as the match ended 2–1. Since returning from suspension, he started in the next ten league matches before being suspended once again. After serving a one match suspension, Kjær returned to the starting line-up against Fiorentina on 24 January 2010 and helped the club keep a clean sheet, in a 3–0 win. He started in the next nine league matches before being sent–off for a second bookable offence, in a 2–2 draw against Genoa on 24 March 2010. After serving a one match suspension, Kjær returned to the starting line–up against Catania on 3 April 2010, as they lost 2–0. He later started the remaining matches of the 2009–10 season and helped the side finish fifth place to qualify for the UEFA Europa League. At the end of the 2009–10 season, Kjær scored twice in a total 35 Serie A games (which was 38 appearances and scoring two times in all competitions).
On 30 June 2010, VfL Wolfsburg confirmed they had opened talks with Kjær. It came after reported interest from teams across Europe, including English sides Manchester United, Manchester City and Tottenham Hotspur plus Italian side Juventus. The move was confirmed on 8 July 2010, as the club signed Kjær for an undisclosed fee believed to be in excess of £10 million. Following his move to Wolfsburg, Kjær said: "The transfer means I have the chance to play for a top club, I think this is the right step for me. We have a strong team that can challenge at the top of the Bundesliga. First, I need to secure a regular place." The deal made Kjær the most expensive Danish footballer of all time. Making the shift from Serie A football to the Bundesliga meant that Kjær would become one of the best paid Danish footballers with an annual salary of around €3 million. Both national coach Morten Olsen and the player, himself, agreed that the move to Wolfsburg was not only economically justifiable for the young Danish defender but also the shift that this was a step in the right direction for his development.
Kjær made his unofficial debut for VfL Wolfsburg in a pre-season fixture against FC Augsburg, in which Wolfsburg ran out 1–0 winners. His VfL Wolfsburg debut came on 15 August 2010, starting the whole game, in a 2–1 win against Preußen Münster in the first round of the DFB-Pokal. He made his Bundesliga debut for Wolfsburg in a 2–1 loss against Bayern Munich five days later on 20 August 2010. After a poor start to the season for Wolfsburg, with varying results and unmet expectations; Kjær scored his first goal for Wolfsburg in a 2–0 win over Stuttgart when he headed the ball in over the line after a corner kick. However, the goal was eventually credited to Edin Džeko after it was shown that the ball took a deflection from Džeko's shot. Despite much criticism from the media for his poor performances, Kjær played in the starting line-up in all 17 Bundesliga matches in the autumn 2010 season. After having formed a successful partnership with Italy international Andrea Barzagli in Wolfsburg's central defence, he then featured alongside German international Arne Friedrich. On 22 January 2011, Kjær scored his first Bundesliga goal with a headed goal in the 83rd minute, in a 1–0 win against Mainz 05, a win that secured the first club victory in eight matches – after seven drawn games in a row. Following Steve McClaren's sacking (who brought him to the club) due to further poor results in February 2011, Felix Magath returned to Wolfsburg (the manager guided the club to win their first Bundesliga title) and commented on criticising the 'poor condition' of the players he inherited (including Kjær) from McClaren. In connection with the dismissal, Kjær declared affection for Steve McClaren in public. Kjær said he was sorry for the firing, and was happy to work with Steve McClaren. Despite the comment from Magath, Kjær continued to regain his first team place for the rest of the 2010–11 season, though it was met by frustration, as the club narrowly avoided the drop the previous season and he had come under fire for some lacklustre displays. Despite being on the sidelines on three occasions during the 2010–11 season, he made 34 appearances and scoring once in all competitions.