The 2010 FIFA World Cup generated various controversies, including some from before the tournament started. Most centred on refereeing.

Qualification France vs. Republic of Ireland

In the second leg of the qualification play-off match between France and the Republic of Ireland on 18 November 2009, French captain Thierry Henry, unseen by the referee and other match officials, illegally handled the ball twice in the lead up to the winning goal. The incident caused widespread debate about FIFA Fair Play, and how matches should be refereed at the highest level. The Football Association of Ireland (FAI) requested a replay of the game on grounds of fairness, but was denied by FIFA under the Laws of the Game. On 2 December, FIFA called an extraordinary general meeting of the Executive Committee to discuss various issues, with the Henry incident high on the agenda. FIFA announced they would be setting up an inquiry into technology and extra officials in the game, but they did not announce a widely expected move of the fast-tracked introduction of goal-line referee's assistants, already being trialled in the UEFA Europa League, and confirmed the competition in South Africa would be officiated as normal with a referee, two assistants, and a fourth official. On the subject of fair Play, FIFA President Sepp Blatter said: "I appeal to all the players and coaches to observe this fair play. In 2010 we want to prove that football is more than just kicking a ball but has social and cultural value...So we ask the players 'please observe fair play' so they will be an example to the rest of the world".

On 5 June 2015 it was determined that the Football Association of Ireland were paid €5 million by FIFA not to protest about Thierry Henry's handball.

Algeria vs. Egypt

The teams finished level on 13 points and level on all tiebreakers: goal difference in all group matches (+5); goals scored in all group matches (9); points in all Algeria–Egypt matches (3); and goal difference in all Algeria–Egypt matches (0). (The away goals rule was not used as a group-stage tiebreaker). The teams met in a one-game play-off to decide the qualifier. To determine the match venue, each team selected a country other than their own (Algeria selected Tunisia and Egypt selected Sudan). After Sudan was drawn in a lottery on 11 November,Sudan to host possible play-off, FIFA.com, 11 November 2009. the Al Merreikh Stadium in Omdurman was selected by FIFA as the venue for the play-off. The decision to play a tie-breaking playoff game to determine who qualifies to the 2010 FIFA World Cup was controversial because despite the fact that Algeria and Egypt were level on all tiebreakers listed above, Egypt would have qualified based on the away goals rule, which was used to determine the winner of a tie in the case of a tiebreaker in both previous and subsequent qualifiers. Algeria won the match in Sudan 1–0 to qualify for the World Cup.

Animal sacrifices Plans to slaughter a cow at each stadium to be used for the World Cup generated concern among animal rights groups. The Makhonya Royal Trust proposed the concept stating the cattle killing event was a "true African" way of blessing the tournament.World Cup stadium 'cow sacrifice' plan sparks row. BBC News website, updated at 16:22 GMT, Tuesday, 1 December 2009.

"We must have a cultural ceremony of some sort, where we are going to slaughter a beast. We sacrifice the cow for this great achievement and we call on our ancestors to bless, to grace, to ensure that all goes well. The World Cup will be on the African continent and we will make sure that African values and cultures are felt by the visitors."

The issue of cattle sacrifice was discussed by a High Court. Judge Nic Van der Reyden said the matter needed to be taken up by politicians.Sangomas sacrifice ox to bless the World Cup stadiums. Cape Times.

An ox was slaughtered at Johannesburg's Soccer City stadium on 25 May. A place was created within the Soccer City precinct to act as a "kraal" where the ox was slaughtered. After that, the senior traditional healers walked into the stadium in song, drum-beating and dance, where they continued to bless the inside of the stadium with rituals.

Group stage

Brazil vs. Côte d'Ivoire Brazilian striker Luís Fabiano handled the ball twice in the build-up to Brazil's second goal, which helped Brazil win the match 3–1. Brazilian midfielder Kaká was sent off late in the game for a collision with Ivorian midfielder Kader Keïta. Replays showed Keïta had run into Kaká's side, deliberately striking Kaká's shoulder, and then fell to the ground holding his face in a successful attempt to have Kaká sent off.

Slovenia vs. USA With the match tied 2–2 in the 86th minute, Maurice Edu of the United States appeared to score the winning goal from a set piece, but referee Koman Coulibaly disallowed the goal and awarded a free-kick to Slovenia. Because Coulibaly had blown for the free-kick before the goal had been scored, he was not required to (and did not) explain the call on the pitch or to FIFA officials afterwards. Replays showed numerous Slovenian players pulling and hanging on Americans, fighting for position in the box, but no foul or offsides by the Americans was apparent to justify disallowing the goal. US striker Robbie Findley was also given a mysterious yellow card, which resulted in him missing the next match against Algeria. Although the match ended in a 2–2 draw, the United States ultimately went on to win the group. Coulibaly received a "poor" performance review for the match and was selected to only one additional match in the tournament, as the 4th referee.

Australia vs. Serbia After the previous two matches, both could still reach the round of 16. However, with Australia having one point and a -4 goal difference while Serbia had three points and a 0 goal difference, Serbia seemingly had the better chance to advance to the next round. During the last minutes of the match, with Serbia losing 2-1, Australia's Tim Cahill clearly hit the ball with his hand in the box, but the officials decided not to award a penalty for Serbia, and play continued;World Cup 2010: Missed handball enrages Serbia manager Page last updated at 22:28 GMT, Wednesday, 23 June 2010 23:28 UKAustralia – 2010 Soccer World Cup, April 01, 2015. also Serbia had a late goal disallowed for what appeared to be a questionable offside.World Cup 2010 final score: Australia 2, Serbia 1. (The Star-Ledger) By Colin Stephenson, on June 23, 2010 at 1:40 PM, updated June 23, 2010 at 10:19 PM With Ghana losing to Germany 1–0, a second goal would have given Serbia runners-up spot in the group and advancement to the Round of 16.

Round of 16

On 27 June, during two round of 16 matches, two incidents occurred that led to renewed debate over the lack of video technology in refereeing"England v Germany: Fifa want 'better refereeing' not goal-line technology", The Telegraph, June 27, 2010"Mondial: le but refusé à Lampard va relancer le débat sur la vidéo", AFP, June 27, 2010"World Cup 2010: Lampard calls for goal-line technology", BBC, June 27, 2010"World Cup 2010: Gordon Smith calls for use of goal-line technology", The Telegraph, June 26, 2010"World Cup 2010: Sports minister joins calls for goal-line technology", The Guardian, June 27, 2010– the disallowing of England midfielder Frank Lampard's goal against Germany, and an Argentinian goal against Mexico that was allowed despite being scored from an offside position.

Germany vs. England

During England's 4–1 loss to Germany, Lampard's shot hit the crossbar and then crossed the goal-line before bouncing back out to German goalkeeper Manuel Neuer. Linesman Mauricio Espinosa and referee Jorge Larrionda did not award the goal but subsequent replays and photographic evidence showed the ball had indeed crossed the goal-line. This incident reignited demands for goal-line technology. This was also significant as England were trailing 1–2 at the time so had Lampard's "goal" have stood then it would have brought England level in the match.

Argentina vs Mexico During the Argentina vs. Mexico match Carlos Tevez scored from an offside position from within the Mexican penalty box when the game stood at 0–0. Although against FIFA's ruling, the screens inside the stadium of Soccer City showed replays of Tevez more than a yard offside when Lionel Messi played the ball towards him. The goal stood, causing uproar and protests from the Mexican players and staff. Referee Roberto Rosetti stuck with his decision. Argentina subsequently won the match 3–1."Argentina 3-1 Mexico", BBC, June 27, 2010 Following the Argentinian goal, BBC commentators wrote that "linesman Stefano Ayroldi [...] somehow allowed Carlos Tevez's goal to stand before a ridiculous situation developed where he, referee Roberto Rosetti and everyone in the stadium watched replays on the huge screens show exactly how far offside Tevez was"; pundit Alan Hansen added: "Before today I was not an advocate of technology in football, but now I am a convert."Argentina - Mexico, BBC, June 27, 2010 Associated Press sports columnist John Leicester reacted to the match between England and Germany by writing: " FIFA fears that technology would undermine the authority of referees and their assistants. But the reverse is in fact happening. Match officials are being made to look like idiots because they are not getting the help that they need. [...] [B]alls, as Lampard proved, can bounce in and out of goal so quickly that a linesman can miss it if he's not paying attention, blinks, is screened or for whatever reason is looking away. That's why technology is needed. And the time to introduce it was yesterday. Blatter has some explaining to do.""FIFA, don't ignore the Blunder in Bloemfontein", Associated Press, June 27, 2010

The press spoke of: "two great victories [...] overshadowed by controversies emanating from two crucial mistakes made by match officials"."World Cup errors highlight need for technology rethink", The Times (South Africa), June 28, 2010

A few days later, FIFA President Sepp Blatter stated that he deplored the "evident referee mistakes" in England vs. Germany and Mexico vs. Argentina matches, and apologised to the English and Mexican football federations ("the two federations directly concerned by referee's mistakes"). He added: "It is obvious that after the experiences so far at this World Cup it would be a nonsense not to re-open the file on goal-line technology. [...] We will come out with a new model in November on how to improve high-level referees. [...] I cannot disclose more of what we are doing but something has to be changed.""World Cup 2010: Blatter sorry for disallowed goal", BBC, June 29, 2010"World Cup 2010: Sepp Blatter says sorry to England for disallowed goal", The Guardian, June 29, 2010

Suárez handball

In extra time of a quarter-final match against Ghana, Uruguayan striker Luis Suárez handled the ball in the penalty area to prevent a last-minute game-winning Ghana goal. Suárez was shown a red card and Ghana's Asamoah Gyan missed the resulting penalty kick. Ghana subsequently lost the match, 4–2, in the penalty shoot-out.