Erling Haaland has cut off the hair that Zlatan Ibrahimovic warned was the source of his strength. The former Sweden striker gave him that advice during the 2026 World Cup, and on Sunday Haaland failed to score in the first game he has played without the long blond hair that had become his trademark.

The 26-year-old Manchester City striker went for a buzzcut before his side's opener against Bournemouth, then went goalless despite having five shots in a 2-1 victory. Before Sunday, he had scored in every Premier League opener he had played — seven goals in four games.

Ibrahimovic's warning referred to Samson, the biblical figure who lost his strength when Delilah cut his hair. But from former Brazil striker Ronaldo to Novak Djokovic, Carlos Alcaraz and Tadej Pogacar, sport's biggest names have produced very different results after reaching for the clippers. Premier League titles, Grand Slams, Tour victories and a World Cup have all followed dramatic haircuts. So have losing seasons, early exits and sharp drops in form.

Haaland had considered cutting his hair after the World Cup, where he scored seven goals as Norway reached the quarter-finals in their first appearance at the competition for 28 years. In the video documenting the haircut, he described the new season as a "fresh start" but admitted Ibrahimovic's warning had left him nervous. He went through with the chop before the Premier League kicked off and called Ibrahimovic, now 44, on FaceTime, only for the former Milan forward to ask if he had lost a bet.

Ronaldo's famous 2002 crop

Ronaldo was 25 when he began sporting arguably football's most famous haircut at the 2002 World Cup. He had spent much of the previous two and a half years battling serious knee injuries, including a ruptured patellar tendon that left doubts over whether he would play at the highest level again, and had only returned to the Brazil team shortly before the tournament. Carrying a thigh problem before France's* semi-final against Turkey and tired of questions about his fitness, Ronaldo shaved almost his entire head, leaving a patch above his forehead to distract journalists.

The distraction did little harm: Ronaldo scored the only goal against Turkey and both goals in Brazil's 2-0 final victory over Germany, finishing the tournament with eight goals, the Golden Boot and a second World Cup winner's medal. Within months he had joined Real Madrid, scored twice on his debut and won the 2002 Ballon d'Or.

A mixed record elsewhere

David Beckham, then 24, arrived for Manchester United's game at Leicester City in March 2000 with his blond hair replaced by a close crop. He scored a free kick in a 2-0 victory, and United went on to finish the season with 11 consecutive league wins and retain the Premier League by a then-record 18 points. Cristiano Ronaldo, then 32, scored twice and assisted another for Portugal in his first appearance after shaving his hair following Real Madrid's 2017 Champions League triumph, before winning a fifth Ballon d'Or later that year.

For Jose Mourinho, the haircut was intended to have an effect before a ball had even been kicked. The then-43-year-old returned to Chelsea for pre-season in 2006 with a number-one crop and said it made his face look "more aggressive," describing himself as "ready for football and ready for war." The season produced a mixed verdict — Chelsea failed to win a third consecutive Premier League title — though they did win both domestic cups, remaining the only club to win those two competitions in the same season.

Beyond football, Kobe Bryant claimed he felt "a lot quicker" after cutting off the afro he had worn for more than five years, and the Los Angeles Lakers completed a third consecutive NBA championship. Michael Jordan shaved his head clean in 1989 and turned the look into one of the most recognisable in sport, going on to win six championships. Andre Agassi, freed from an anxiety-inducing hairpiece, produced the most successful season of his career by beating Pete Sampras to win the 1995 Australian Open. Novak Djokovic, after shaving his head with his Serbia team-mates in 2010, began 2011 by winning his first 41 matches and taking three Grand Slams. Carlos Alcaraz, 22 when his brother made a mistake with the clippers before the 2025 U.S. Open, beat Jannik Sinner in four sets to win his sixth Grand Slam and the world No 1 ranking.

The theory even reached the peloton, where Pogacar opened his season in March by winning Strade Bianche for a record fourth time and later won five stages and a fifth Tour de France title after joking his cut made him "more aero."

A word of caution for Haaland

The anecdotes appear reassuring for Haaland, but Patrick Mahomes provides a strong reason. The Kansas City Chiefs quarterback was 29 when he shortened a hairstyle he had sported throughout a run that brought three Super Bowl victories, and admitted there had been an element of superstition behind keeping it. After losing to Philadelphia in February 2025, Mahomes finally went shorter — and the Chiefs went from a 15-2 regular-season record to 6-11, missed the playoffs for the first time since 2014, and recorded their first losing season in 13 years as Mahomes posted a career-low passer rating.

Ronnie O'Sullivan's experience was also mixed, while England cricketer Chris Lewis developed sunstroke and missed an opener after Duncan Fletcher's* team-mate shaved his head on a West Indies tour for charity. Haaland's experiment is still only minutes old — but out of his five shots against Bournemouth, only two were on target, and his failure to score ended a run of five consecutive Premier League appearances in which he had found the net.